What is wrong about making machinist good?

[Shurrikhan]

I disagree having one of the two charges be single target while the other is AoE with the same potency.

And yet that's what we had from the class's start in Heavensward all the way up until Dawntrail without issue?

One is meant to be situationally but objectively better than the other. Just as Chainsaw is situationally and objectively better than Drill even in terms of direct damage alone. They do not share cooldowns, so what would be the harm in that?

what I would have envisioned for both charges would have been something similar to Fan Dance, where heat blast regens gauss round as normal, and using gauss round has a chance to proc ricochet, for example.

I feel like 90% of the point of Heat Blast is just to enforce a 1213121312 rhythm between it and alternatingly Gauss Round and Ricochet. Is that a button-flow you dislike, or...?