I'm there too... her night sleep isn't too bad but the naps are SHORT!
If she wakes up happy, I leave her be... if she is grumpy, I try to put her back to sleep. I try for 15-20 minutes, then I let her get up... if she continues to be grumpy, I let it go for another 20-25 minutes and she goes down for a nap again. This is the only way I maintain my sanity.
I can't seem to extend her naps and even with short naps, it doesn't affect her night sleep so... why mess up a good thing?