I think the LLC is the best faction in the game overall. They have the coolest theme (super rich, futuristic steam punk? Yes please!), they have two powerful supports in Kleese and Kid Ultra, Phoebe can be played as either a tank melee or a hit and run assassin, Marquis is the best pure sniper in the game and to top it off, they have a giant murderous robot. El Dragon’s late game is literally the most fun character to play.
If there is one area where I think they are lacking, it is mid-range skirmisher, but you could make a case that Phoebe can fill this spot, particularly with helix choices Shield Resonators and Contingency plan, allowing for quickly closing any gaps and making hasty retreats.
ISIC is not the typical tank, but he is the typical artillery piece, specifically once his ult unlocks, it reminds me of old Mechwarriors games.
What do you think? Is there a better overall faction? Design wise, play wise? Just to head it off at the start, Eldrid are not a better design, sorry.