Makena isn't ever very crowded, however there are some big rocks in certain spots, but are easy to avoid. This spot has very very good sidewash and is often not crowded if you go during the afternoon. Kaanapali has a very powerful break and a variety of tricks can be preformed Right in front of the Kaanapali Alii Hotel, Westin Hotel, and even down by the Hyatt Lahaina Good beachbreaks all the time. First BIG swells of winter and summer are the best. Incoming tides are the way to go.
Crowds suck, alot of rich assholes who think they own the beach.
Turn left at Kaanapali and look for the Condo Kaanapali Ali'i. Go to a beach access at the Ali'i or at the Marriot. That's OK though, more skim waves to go around. These are mostly State or City beachparks which are all listed on maps. I live on the north shore of the island of Oahu.