CW-X just came out with a ventilated full-length tight, that has mesh panels on the quad and calf, and is overall lighter than the regular Stabilyx, but still has very good compression.

I just got mine last week. To me, they were still a little bit warm for running in 70°F (with a very light top), but I think they'd have been fine for cycling temperature-wise, even several degrees warmer.

I can't quite see wearing compression tights on the bike - just because for me, when the chamois is held so tight that I'm suspended above the saddle, it's as bad as having it too loose - but it might be an option for you.