1. Latency, the elephant in the room
Stormblood MCH suffered a lot from latency derived issues that prevented a lot of players with mediocre or even average latencies to play it fully without using an alternative, suboptimal rotation. This was of course due to flamethrower use / interrupt and double weaving abilities, but the main and major culprit has always been rapid fire and its 1.5s GCD. When Square Enix says that the game can be played up to 200ms of latency, well, I guess it depends what you mean by "playable" I guess. For most of those players, it feels horrible.
Shadowbringers MCH brings the Rapid Fire back with 4 times more uses every minute. How could that even pass the design process and not be scrapped considering the pain and stress it caused to players in the previous expansion already? Why are we still dealing with that? Do we have to all move within 1000km of game servers to finally stop stressing ourselves out over this? Why weren't MCH players actually listened for the countless feedback we gave about that critical issues for TWO YEARS now? You chose to remove ammo instead, nobody considered ammo to even be a problem. Rapid Fire is.
Just remove that mechanic or reduce the amount of stress it puts on internet connections and server distance. This is just not sustainable. I'm open to many suggestions, like increase the GCD speed to 2s with heat blast instead of 1.5s, and adjusting potencies accordingly. This could go a great way to still retain the speed increase burst identity of the job without making it absolutely unfair for half the globe.
I have dealt with that for two years now, and while I moved servers now and am perfectly fine, I know how it felt. And as a a personal feedback on which many will probably agree, it feels AWFUL when your latency doesn't follow.
2. Hypercharge and carpal tunnel tedium
We spend our time being literally using Hypercharge and overheating, spamming heatblasts like madmen by weaving an ungodly amount of abilities (our 2 charged abilities, Gauss Round and Ricochet), which also get recharged faster by using Heat Blast. Close to half our time is literally spent under overheat doing that. I like the concept behind Hypercharge because it fits MCH job identity, which is about big bursts of targeted damage.
I don't like at all how it was implemented in Shadowbringers. For one, we spend our time doing that and it feels incredibly repetitive, taxing and boring fast. It's actually tedious for me now and i'm not even max level. Second, it doesn't even feel rewarding. We literally spamm abilities with mediocre damage and awful numbers (which is understandable considering the insane amount of hypercharges we have to use with so much generated heat). I have always considered MCH identity to be about big, meaningful, rewarding bursts of meticulously applied damage every minute (tied to the old wildfire). Those hypercharges feel like anything but that.