There's a rather effective hybrid build for Kayle on LeagueCraft (Might be here as well), where you can easily get the maximum CDR.

With max CDR.. your RF lasts 10 seconds.. and has a cooldown of 10.8
0.8 seconds is good enough for me.

As a tier 1 champion, I say she's fine. Her heal is pretty ****ty, though, and should be made to weaker than Soraka's, but not too much weaker. Her ult is okay- not the best ult in the game, but it can save lives. Her "E" is so pro if used right, and her "Q" is good for many reasons.

If they buff her heal, I say she's fine.