Speed and the wildfire windows are one and the same. If you do not have a problem with the speed, you do not have a problem with the Wildfire window.
As for the Heat Blast spam, if that is all you are doing, you are doing it incorrectly. The Heat Blast window contains three buttons that are pressed in quick succession as to maximize DPS since each Heat Blast lowers the cooldown of Ricochet and Gauss Round. Overcapping on either of those two means you are losing DPS.
I struggle to understand to understand how Heat Blast can be "mundane" when it is arguably one of the most high intensity part of MCH rotation, especially during heavy movement.
It sounds mean, but at some point if they want to introduce a "quick" job, they will have to design it in such a way that high ping players will never be able to maximize. There is nothing wrong with having one job that is ping unfriendly.
MCH has never been more popular, which speaks volumes. It's understandable that people might miss what it used to be, but frankly the numbers speak and the direction MCH went is healthier.
I would actually like it if Wildfire was on a 60s CD, since now I feel like it lines up pretty funky in certain fights.