Or how about:

Heat Blast:
Additional Effect: Reduces the recast time of Gauss Round by 30s and Ricochet by 15s

Auto Crossbow
Additional Effect: Reduces the recast time of Gauss Round by 15s and Ricochet by 30s

This would have a similar effect, in that in single target, you can just hop between Heat Blast and Gauss Round, and similarly for AoE, Auto Crossbow and Ricochet.

It might be a bit too OP for AoE right now, but as a trait upgrade in 6.0 post level 80, it could be good.