-Heated Shots should be gaining potency based on current heat level.
-Flamethrower should be an AoE version of Cooldown. Needs to also be usable while moving, with a speed penalty. Also needs to allow us to adjust facing.
-Wildfire needs to be Charge based. (Example being Wildfire would have 10 stacks on the target, each shot triggers a secondary explosion for 25% of the shots damage and removes 1 from the stack, Only Core Shot skills trigger it, Not Ricochet/Gauss Round).
-Wildfire could potentially have its recast reduced or reset when consuming Heat via Cooldown. Alternatively, Adding a charge of Wildfire to the target.
-Reassemble does not appear to be eligible for Direct Crits, It crits for the same value on Clean Shot always (i could be REALLY unlucky though)
-Rapid Fire should be a trait proc instead of a cooldown. Same effect, proc chance when triggering Slug or Clean Shots.

Right now, We are incredibly dependent on lining up 4 cooldowns every minute in order to achieve "optimal" Wildfires. No other job is as dependent on a single button as MCH is to Wildfire for damage.
I don't even know how we'd go about changing that.
But a good start would be to make Wildfire a core mechanic that interacts with our other abilities beyond "Press Wildfire and every cooldown every 1 minute or you're doing it wrong".

All the other DPS Jobs have central mechanics that enhance the identity of the Job.
Dragoons have Blood and Life of the Dragon, Ninjas have Mudras, RDM/BLM have their unique spells, Summoners with Pets/DoTs/Bahamut, SAM has two core mechanics and even Bard feels very much like a bard constantly singing songs that buff the party.
What does the MCH have as far as a mechanical identity? Nothing really, unless you count being the only job with a random proc 1-2-3 combo.Turrets are just set and forget auto attack bots. Wildfire could be that mechanic, if the developers would only get creative with it.