I agree, as soon as I saw the media tour MCH rework for Shadowbringers, it felt like that nothing in the kit actually interacted with each other much, it's just a bunch of high damage tools to use on cooldown, and the gauges don't interact with each other either. What generates heat and battery is totally arbitrary with little meaning behind.

Flamethrower literally conflicts with the rest of the kit and they had to finally, finally buff it enough to offset the fact that it's not generating anything for your resources.

The hypercharge 20 potency increase of blazing shot is a leftover from what overheat used to do before ShB (+20% damage output), just a lot more shallow because of its inconsequential power and it's meaningless past the first few level as soon as you unlock heat blast that you just want to spamm (so they could have just baked the potency into heat blast instead of this), where it could have had meaning on the filler combo like it does in the first few levels.

Wildfire used to be a million times more interesting when you could actually choose what to put inside and how, especially since the job had ammo rng to not make the sequence a fixed optimal thing to always aim for, which was a unique signature of the ranged physical role that only BRD and DNC somewhat still have... somewhat. Right now, WF isn't tied to overheat, but it's like it could either way because it wants you to use it while spamming blazing shot anyway. The only thing it still allows is desyncing from hypercharge it back or forward by one GCD though, which can allow some flexibility and some burst techs (like, WF -> GCD -> Hypercharge into blazing spamm or Hypercharge -> Blazing -> WF -> Blazing spamm -> 2x GCD). I wouldn't want to lose this because that's essentially one thing they kept from the predecessor of hypercharge, which was Rapid Fire (next 3 GCDs are fast recast). The main difference is how many shots are fast recast and that you can't choose which weaponskills get into it.

The self buff that MCH used to rely on in HW was an infamous combination of many (Raging Strikes, Eagle Eye, etc), which was overbloated. I do feel the best iteration for its self buff was Overheat in SB with the +20% when you would overheat the gauge, even though the way to overheat it was too clunky and finicky/latency dependent. I'd rather have them go back to something unique like this instead of a fire and forget button that half the DPS roster already have.