EpisparhPlasma FTW! ....unless you go the dumb rocket stuff for effectives.
For sidearm - Tormentor. Always!
For primary - Executioner for mission running. It works also in CZ but you will need practice. For CZ you either go with double Intimidator combo and run amok Duke Nukem style. There is middle option of the hybrid approach of Executioner/Intimidator.
And do not bother with Oppressor - it is pure trash.
Laser/Kinetic is mostly a PvP stuff , IMO.. Lasers are hitscan and kinetic is almost same, while plasma is easier to dodge even in close quarters fight.
I personally prefer the plasma because you need to "predict" the shot.
Found a grade 3 Tormentor with faster reload, and a grade 3 Dominator suit. No luck with main firearms yet. But I'll keep looking.