I mean I could understand hitting a wall creativity wise if it wasn't for the number of different fixes that I have seen others and myself post that could be done flavor wise and in a lot of cases function wise. I think the MCH started more like an engineer or gadgeteer that used a gun and then in ShB they kind of switched it to a gunner class and that's where they ran into issues. Which a gunner class could work if it had been built that way from the beginning.
I believe to fix the creativity problems and some of the issues they should go back more towards the gadgeteer side of mch. Give us our turrets back and give the support thats needed and move away from the "selfish dps" because they havent figured out how to balance it and ranged tax. Create skills and abilities that dont revolve around the gun. A gap closer that functions like a grappling hook or "rocket boots" that launch us to the side, a party or personal shield that is created by a smaller turret thats thrown in the air and lasts for so many seconds, turn flamethrower into a turret that you throw out and does a 360 aoe, tie the heat and battery gauges together and make them more synergistic and useful.
This post has some great ideas on how to tie the heat and battery gauges together. https://forum.square-enix.com/ffxiv/...Machinist-post.
I think they need to bring an actual Gunner job in and have it focus on being a pure dps with skills and abilities that tie into that instead of shoehorning mch into it and let mch be the counter support job to brd and dnc. I like to think of the balance for r-phys like pre-EW healers. WHMs were regen, sch were shields and ast were the balance in between. Brds are all about buffing dmg and heals, dnc seems like a good balance of buffs and mitigation, let mch be the damage mitigators, let us be the shields of r-phys. which would fit more flavor wise. MCH dont use magic, but we do use machinery; energy and mechanical shields exist in the game already so it wouldnt be taking things any farther into sci-fi