I've been to Tahoe many times, and have been to more than 1/2 the mtns there multiple times. I really love Squaw & Northstar at their respective ends of the lake. I hear Kirkwood is amazing for snowboarding, so that is the one I have yet to get to just because it's so far South and away from everything else on its own.
What do mean by 'respective ends' for Squaw and Northstar? They are pretty much in the same corner of the lake... The drive between them is a little inconvenient but still only 20-30 minutes IIRC?