Flower trails are incredibly ugly and intrusive, and they really need a replacement. Not sure what though...

A low intensity particle effect?
Alternately, something like the flower trail, but only put down one random flower/sparkle/whatever (out of like, 16 patterns?) every block you travel. For bonus points - make the distance traveled per flower/sparkle/whatever a locally configurable effect, with zero disables (for the folks who don't like anything). It's really just a client-side decoration anyways.