Should leveldesigners even bother with that?

I mean, if you make a map lori friendly its likely to have very easy jumps which is gonna make the difference between very good spaz players and lori players a lot smaller.
I mean, spaz is mainly the rule for most levels.

But you could try to make a "jazz-only" level. A level where hovering would be so crucial u couldnt use spaz in it. We would get people using jazz/lori again, and you wouldnt have to worry about making the level fit 2 very different types of characters - Spaz on the one hand and Jazz and lori on the other.