— Quality of Life and UI ----
Disable Opening Movie option : Simple enough, an option in the settings menu to disable the playing of the opening movie upon loading the game.
----Gameplay, Enemies, Levels and Shrines.-----
Make Rainstorm A Viable Option - Currently you can unlock everything in the game in either Drizzle or Monsoon, but there is no reason to simply play on the games base default difficulty, at least for unlocks. I suggest that any new items, characters, abilities and loadout options that are added be required to be unlocked on Rainstorm specifically.
New Map Concept - Crater : Meteors Fall, A large crater/valley like area with a huge bubble/meteor in the middle obstructing view of the entire map at once. Basically the edges of the meteor and the edges of the crater slope are filled with rocks and debris to break up the smoothness and obstruct vision. This would be an alternate First Stage alongside Titanic Plains and Distant Roost
New Map Concept - Hive : Arachnids Lair, An underground map in the same type as Abysall Depths. Darker and lit with glowing fungus and hive structures that have bioluminesence. New enemy type spawns here , wall climbing arachnids that attack you from where they are clinging with web spit that hurts you and slows your movement. This would be an alternate Third Stage alongside Rallypoint Delta and Scorched Acres.
New Map Concept - Ruins : Temple of The Moon, Using the same architeture that is seen on all of the other levels in the form of ruins, but in a more uniformed manner in one giant temple like structure with defined platforms and passageways. This would be an alternate fifth stage alongside Sky Meadow.
New Artifact - Artifact of The Prism, The stage order is randomized, the fifth stage every loop always contains the Primordial Teleporter, regardless of if the stage is Sky Medow or not. This also means you could get two of the same stage variations in the same 5 level loop, like Titanic Plains and Distant Roost being in the same loop.
New Enemy Type - Rogue Nanites - High Difficulty spawn, around the same time the Void Reavers start to show up. These appear as blobs/clouds of tiny specks that can not be damaged directly. They will seek out and cling to any non-player ally or unactivated drone nearby. Once attached, they clone the drone/ally and detach to become a duplicate of it that you must attack.
New Shrine - Shrine of Rebirth, Rare find on a map, Costs a fair amount of money at current diffulty, on par with Altar of Gold. Is only interactable if a player is currently dead. Upon activation any players who are currently dead, are resurrected at the shrines location to continue playing the current level. One time use per shrine.
New Shrine - Shrine of Chaos, During the Teleporter Event, the Red Sphere for the teleporter activation moves slowly about the map (following normal walking enemy AI pathing so it can’t go somewhere players can not.) Players must remain inside this to activate the portal, but as it is moving it becomes a fair bit more difficult. Upon success, all players gain double xp from the final coin-to-xp tally.
New Altar - Altar of Weakness, During the teleporter event, players only get 50% of the effect of any items they have. For example, if they have 10 armor peircing rounds, they would only get bonuses as if they had 5. At the end of the event, normal item bonuses are restored. Success while completing this altar gives each player one extra item, much like the Challenge of the Mountain does.
---- New Items ----
Enhanced Items - Every item currently in the game should get the ‘chance to find a better tier version’ treatment. For example, the white tier item armor piercing rounds, could have a 0.1% chance to appear as a green version that give 3x the normal stack effect. For the rest of the run this item counts and works as a green tier item for scrappers and 3d printers. This also allows a new type of machine/chest to be added to levels called the Enhancement Chest. Costing a lunar coin, one of your held items will be chosen at random (with lower tiers being more likely to be grabbed, and higher ones being very very less likely but possible) and converted into an enhanced version. White->Green->Yellow->Red. Red Items can never be enhanced. Gives another use for lunar coins.
Piggy Bank - Green Item, Every time you gain money from kills or capsules, you store 1% per stack (minium 1 per kill per stack, maximum 50 per stack) of them in the piggy bank and it is unusable that level. However, at the start of the next stage all stored money in the bank is ejected and you can use it. Stacking increases the percentage and minimum saved.
VIP Security Card - White Item , All interactable costs are reduced by 1% cost per stack.
Growth Tonic - Equipment, Targeted enemy increases in size by 1.15%, and doubles its stats, gains or doubles elite bonuses, etc, but also doubles xp and coins dropped. 60 second base cooldown.
Recall Device - Equipment, All allies under your personal control are teleported to your current location, including the stationary turrets.
New Abilities/Loudout Options
Primary - Headshot , Shoot Once for 180% Damage. 360% damage to stunned enemies. Half the attack speed of his normal Primary. Has no damage falloff range (but a total max range of 80m). Unlocked by stunning 20 enemies within 3 seconds while on Rainstorm Difficulty while playing as the Commando.
Secondary - No New
Utility - Combat Slide , Slide on the ground for a very short distance, sliding through enemies has a 50% chance to stun them and deal 25% normal damage. You can fire while sliding. Unlocked by rolling or sliding through 15 enemies in one motion while on Rainstorm difficulty while playing as the Commando.
Special - Fortify , For 5 seconds, Reduces all recieved damage by 50%. Reduces movement speed and jump height by 50% each. 20 second cooldown. Enter the teleporter on Abyssal Depths, Sirens Call or Sundered Grove without picking up a single item on that stage while on Rainstorm diffuclty Difficulty while playing as the Commando.
Primary - Launcher Pods , Fire a series of 4 dummy-fire rockets. These rockets fly at a high rate in a straight line and explode on contact with an enemy or wall for a small explosive area of effect. Slow to reload, these rockets do 150% damage each. Unlocked by playing Abandoned Aqueduct or Wetland Aspect from start to finish without placing any engineer turrets while on Rainstorm Difficulty while playing as the Engineer.
Secondary - Upgrade Drones , Tosses out a small flying support drone. These drones detect any nearby mechanical ally and attach to them, generating a single hit shield around them and providing a 10% damage increase to their attacks. After the protected ally takes any amount of damage, the drone is destroyed. You may control up to 4 at once. Throwing a new one once 4 exist will destroy the first you threw. Only one drone will attach to any one ally. Unlocked by having 10 white scrap, 5 green scrap and 1 yellow scrap in your inventory when you enter the Primordial Teleporter as the engineer on Rainstorm difficulty while playing as the Engineer.
Utility - No New
Special - TR66 Bunker Turret , Cooldown 20 seconds. Place a stationary turret that inherits all your items. Fires a slow fire Rail cannon for 500% damage that hits all enemies in a line for 60m and occasionally fires a rocket barrage of 10 homing rockets for 10% damage each (More for proccing item effects than dealing damage), can place only 1. Unlock by having 400 minion kills on Rainstorm Difficulty while playing as the Engineer.
Primary - No New
Secondary - Focus, Cooldown, 10 seconds. Targeted enemy is now focused for 7 seconds, all damage recieved by this enemy from the huntress or her minions is increased to 250%. With the Backup Magazine, multiple enemies can be Focused. Focusing again on the same enemy will add 7 more seconds to it’s active Focus timer. Unlocked by killing 50 enemies in a row without using your secondary attack once while on Rainstorm Difficulty while playing as the Huntress.
Utility - Phase Out , For 3 seconds per use, You become completely un-damagable, but can not us your primary, secondary, or special attacks. You jump twice as high as normal and fall slowly while phased. Unlocked by having two stacks of Shaped Glass while playing as the Huntress and completing any one teleporter boss fight from start to finish while playing as the Huntress on Rainstorm Difficulty.
Special - Counter Attack , Fires a powerful single target shot which utilizes all recently recieved damage to determine it’s output. Taking any damaging hit increases output damage of this ability by 100% of that damage total recieved. There is no upper limit on the possible amount of saved damage, but using it will set it back to 0. This amount is not reset by passing from level to level. Unlock this by surviving a direct hit of Mithrix, King Of Nothings ground smash shockwave while playing as the Huntress on Rainstorm Difficulty.
Passive - Environment Suit , The Loader is immune to fall damage, and has a 75% chance to ignore enemy created debuffs. Unlocked by obtaining 5 different stacks of debuffs on yourself while playing as the Loader on Rainstorm Difficulty.
Primary - Bladed Gauntlet - Proc Coefficient 1.25. Swing at nearby enemies for 280% damage, 50% of this damage ignoring armor. Unlocked by completing 20 stages in a single run while playing as the Loader on Rainstorm Difficulty.
Secondary - No New
Utility - No New
Special - M551X Overclocked Pylon . Cooldown 60 seconds, Proc Coefficient 1.25. Zaps up to 10 nearby Enemies for 60% damage. Can be Grappled. Unlocked by placing an M551 Pylon near an Overloading Worm while on Rainstorm Difficulty while playing as the Loader.
Passive - Support Microbots , Duplicate 50% of the healing you recieve and send it to an ally at 30m range prioritizing the ally with the least amount of health. Unlock by using the Foriegn Fruit, Super Massive Leach and the Gnarled Woodsprite at least once each in a single run on the Rainstorm Difficulty while playing as the Captain.
Primary - Magnum , Slow Fire, Proc Coefficient 1.5. Extreme knockback on smaller enemies. Fire a single shot that deals 500% damage. 800% damage to Bosses and Elites. Unlocked by Beating the game on Rainstorm Difficulty while playing as the Captain.
(I kind of ran out of time on the day I was writing this to continue making more ideas to add to the list. So I will add to it when I have some time. For now this is what I have.)