SF4, 5 and 6 for me are really ugly. As the series go on the characters become more deformed and weirdly muscular. I like the more anime/slim artsyle of SF Alpha and III more.
Hot take:
Games; mainly platformers, with respawning enemies have always been horrible and very annoying, especially if they don't stop respawning or respawn just after you've killed them all, left the screen for a moment and come back.
Enemies with respawns only work in games with grinding and levelling, such as RPGs, or if they drop consumable items.