MCH I think is going to be needing a DPS buff with all this talk of SMN/RDM buffs going around. If it doesn't then it will likely be pushed to the sidelines in end game for double caster meta. For MCH a couple of things should change.
1) Queen needs to work with Wildfire. Its attacks should be treated the same as your own to stack up wildfire, the fact that it doesn't just bewilders me.
2)Reassemble should have an instant animation. Many times do I find myself ending a hypercharge with a drill ready and reassemble but no matter how fast I hit my buttons there is always a delay on the drill. The problem is 100% reassemble because without it I can get off an Air Anchor or a Drill after a hypercharge fairly easy.
3) Guass/Ritchotet feel like they need the buff. I don't think Heatblast needs the potency but guass/ritchotet do. 150 potency doesn't feel impactful enough to make me want to use them outside of hyperdrive simply because you spam them in between heatblasts. They don't feel like an important core. I think changing them to 200 potency would be perfectly reasonable.
4) What is really the point of flamethrower? Sure its a DPS gain if you let it run on two targets for 3 ticks but I mean who really does that?