This is definitely well intentioned, but I think there are some assumptions that a lot of people are making about the master tree that really skews the perception of what is actually wrong. For starters.
That is not necessarily true.
Pet builds are underperforming in my, and many other people’s opinions. That doesn’t mean that the Master Skill tree as a whole is underperforming though. Gamma Burst builds focused around tanking or gun damage are actually gaining popularity, and are looking to be very effective in Mayhem 3 for their mixture of tankiness and DPS that the post-nerf crit builds don’t have. The Master tree has a surprising amount of gun damage boosts in it, 132% to be exact.
Especially since the buff to Barbaric Yawp, it can be paired with either other tree to add extra survivability or damage.
As a pet tree, master needs work. But as a FL4K skill tree, it works well. That brings us to point number 2.
Once again, this is close, but not the whole story.
The master skill tree has over 140% damage for the pets not including Gamma Burst, as well as He Bites and Atomic Aroma for nice passive DPS just by existing. The tree provides more than enough damage for the pets. It is the pets themselves, the base skills, that lack the damage to scale the Master skill tree to usable levels. Outside of tripling every pet damage related skill in the tree, no fix to the skills as they currently exist would make the pets perform better.
That is where the issue with Dominance comes in. It may have its quirks, but because the pets lack sufficient base damage to scale the Master trees buffs to a usable level, the only way to make pets do damage is by turning enemy damage against them. He Bites is one part of this formula. Dominance is the other. By converting an enemy to your side, you can take all of the enemy’s damage with you, instead of the at most 40% you get with He Bites. Regardless of how the AI derps out, even if they are only active for a few seconds, they will likely out damage your pet in any equivalent time frame.
Many people seem keen to change Dominance to pet another pet on the field. I think that would be a horrible approach. Until pets, at their base level, get buffed, 2x0 is still 0.
I don’t think anyone would anyway. Aside from the Dominance ironically working better with Fade Away than Gamma Burst (invisibility to get the melee attack off, don’t need to waste a slot on Face Puncher), as you said, Dominance doesn’t synergize with Master in the conventional sense.
Dominance is basically a bandaid for poor pet scaling. It’s more akin to Close Enough covering for Anarchy accuracy loss than a synergy like No Kill Like Overkill and Money Shot. Unlike close enough, it basically exists independently of the pets, making it so that you could play without having a pet equipped and Dominance wouldn’t function differently. If your goal as FL4K is to make YOUR pet as awesome as possible, Dominance won’t appeal to you. And if you are going down Master for a gun FL4K, then Dominance does nothing for you anyway, so why bother? It’s a pretty small niche that would take Dominance just to have ANY friendly NPC fight alongside you, as we can see from how many people hated Thoughtlock.
As stated earlier, master skill has 132% total gun damage. A lot of it is available by tier 2. You can get 47% damage for 10 skill points. (and an Action skill, an augment, and a pet to be fair).
If your goal is tanking, you don’t need steep investment either. For 14 points, you can get 15% damage reduction and a near permanent 2% health regen per second.
Next to Stalker, Master is the tree you need the least investment in to get massive QOL.
Lastly,
Any extra damage or stats to the pet should be baked into the base skill. That is just about all that is needed to make Master pet builds viable.
But to your question about how to rebalance the tree, it seems that Gearbox is pushing for Gamma Burst to work like Axton’s Turret, making the skill and pet provide the player with bonuses for having it active, while not contributing a lot of direct damage on its own. This isn’t too bad, if not for all of the damage bonuses for the pet giving the impression that you can make it a significant portion of your DPS.
So I would make a stupidly simple change: Make a skill (maybe replaced Shared Spirit) that makes enemies FL4K targets for attack commands take extra damage. Basically, give Fl4k laser guided. That way you have a skill that buffs both gun and pet builds equally, makes use of a currently underutilized mechanic, and contributes to all of the strengths of the Master skill tree; support builds, gun builds, and pet builds.
Super long winded. I apoloigze.