I kinda feel like I accidentally trivialised the game without trying.
My build was very lightweight and I dual wielded that one full auto pistol you can get very early on (After the first or second proper mission). Then I put a laser cannon on by shoulder and the lightest rocket pod for maximum speed/dodges.
For FCS I just picked the one with the highest close combat stat.
The general tactic during a boss or enemy AC fight was the following:
Just hold down 3 of the 4 shoulder buttons (2 pistols + laser cannon) the entire time and shoot the rockets as soon as they're off cooldown.
Don't even bother about aiming or so, just get in the enemy's face blasting on full auto the whole time. As soon as you break their stance,RELEASE the laser cannon shot for big damage.
This strat was so incredibly braindead because it frees up all of your attention for dodging but it was so effective at the same time.
I first tried so many bosses with this build. Only when I faught the Balam leader I had to switch loadouts because the pistol ammo would run dry, not because I was getting killed.
Especially in 1v1 Arena mode fights this was unstoppable.

I had great fun but going online and seeing people having trouble beating bosses I felt like my build was just by accident completely OP and I though the game was just that easy.