@OP
It's like you've taken a coin with either side viable, and instead landed it right on its edge for an untenable position.
I agree that we both should and likely will lose our awkward click-and-quite-nearly-forget long maintenance buffs, but why would you, in lieu of that, suggest baking the buffs into another skill, let alone one that would, say, put DRG rotational priorities in direct conflict with themselves?
We're facing button bloat, but button bloat only has at most half to do with actual button count. The majority of it has to do with efficiency: how much gameplay--how many distinct rotational strings and tactics and strategies--can we form from the given buttons?
DRG's weaponskills allow for essentially 3 rotational strings in Single-target combat, with only a single decision path. I'd much rather see as many keys as we have now, or even a few more, with considerably more depth to each than to remove what little complexity we have as outlier to the doldrums of the majority of our keys on combo classes.
Likewise, MCH is hard-pressed to find variance, flow, or any real excitement from its weaponskills, even with the augmentation of Ammunition and Gun Heat -- the latter of which manages to feel far more esoteric and punishing than it feels exciting, intuitive, or wholly integral -- and in need of a more integral tool to let its systems compliment each other. Rather turning Hot Shot into a trait, taking with it its impact on and within Ammunition, why revise to aid the solution to Gun Heat's underwhelmingness?