Also, what's a good supplimentary weapon for these things? I don't mean something that can cover range, do standard damage, I mean what works well together with plasma weapons?
For the IS Plasma Rifle:
- AC/10s and their kin. Low heat, same solid damage, similar ranges. I like the LB-10X more than the AC/10 and the Ultra-AC/10. It's more flexible and longer-ranged, and like the Plasma Rifle it's good against Vehicles.
- LRMs. Fairly low heat, long range, decent damage and a good spread between crit-seeking and armor shredding ability. MMLs are good too for the same reasons. They complement the Plasma Rifle well.
- SRMs. Critseekers with standard munitions, or another heat weapon with Inferno warheads. This applies to MMLs too.
- Additional Plasma Rifles. Putting all that extra heat on an enemy mech can really mess them up.
- PPCs. Similar reasons to the AC/10; they're hotter, but they are lighter too so you can add double-heatsinks to cope with that for the same weight.
- Medium Lasers. One of the most efficient weapons in the game.
For the Clan Plasma Cannon:
- Since it generates a bit less heat and is much lighter than the IS Plasma Rifle, you can combine Plasma Cannons with pretty much whatever you want. Since they don't damage mechs at all they are more like supplementary weapons on many designs, or carried in bulk on some infantry/vehicle hunter designs.