Not necessarily the fire effects for the entire game, or really for most of the staff effects. I'm talking more about the burning particles on enemies when inflicting fire damage (whether by staff or weapon), or the coruscation staff's secondary attack. I just generally think it looks bad, and as far as fire attacks go, pretty non-cathartic. Hell, even an audio replacement to give it some extra sizzle would be nice.
Again, not for the effects the rest of the game uses, such as idle burning buildings or maps, etc. Just for what Sienna does, as a QOL mod.