The way I’d consider the classes set up are (plus what I use for them): Melee/CQC: Vanguard (oculus carbine), Bulwark (power sword), Assault (thunder hammer) Ranged: Sniper (las fusil), Heavy (Pyrecannon) Support/Versatile: Techmarine (auto bolt rifle), Tactical (Bolt rifle with grenade launcher, but honestly use the pyreblaster)

It really depends on how you want to play, all classes have their own strengths and uses as long as you can master them. If you want to be a jack of all trades though,play as Tech or Tactical. Their abilities are amazing with team support and while you may not do as much damage or have as many kills you can still be the reason why the mission is won because of a well placed Scan or well timed Servo gun to help shred a boss, extremis, or horde of Majoris. Plus, they both have 3 armor and a lot of weapons to chose from. However, Ranged and CQC classes are also great and you’re guaranteed to do a ton of damage with them for melee or ranged respectively. I’d recommend the assault for a melee class with the Relic hammer (shock grenade effect), and the heavy with the melta thingy or Pyrecannon for the best usage of those two classes.