My main problem with flying is how clunky and cumbersome it is. And a faster mount won't improve of any of my complaints:
Camera is too close to enjoy the scenery, stick down to go up, x to speed up (so forced to use the crab method to use the right stick), random camera moves (forcing me to constantly use the right stick to see exactly where I want because of super restricted FOV, but then you can't press X to accelerate).
All of that making it really not enjoyable at the point of actively findings ways to avoid using the flying mount (running, ground mounts or ideally teleports).