Being that I use the bike trails often,a frame mount for me to the eyes of others makes the bike look very close to a motorcycle.
It does balance out the bike a great deal,but for the bike trails I'm actually more accepted (not just feel more accepted,but really am more accepted) when I ride my titan kit.
So my opinion,I would love to see an improved frame mount,but my rack mount makes my bike look more like an engine assist bicycle and less like a motorcycle.
At least when I'm approaching roadies,they cannot tell my rack mount is engine assisted.