Sometimes you get the urge to do a touristy thing, but you really can't handle crowds. Avoid Six Harmonies Pagoda, Lingyin Temple, and Leifeng Pagoda if that's the case, and take a stroll on the South part of the lake. There you'll find Qian Wang Ci. The reason there aren't as many people is that it doesn't have as much historical significance as the others. It's a memorial temple to the kings of the Wu Yue kingdom who ruled this area for a whopping fifty five years between 923 AD and 978 AD when the last king handed over control to the Song Dynasty. This spot has had temples built and destroyed on it for centuries. Three times it was erected as a memorial to King Qian, the final time being in 2003, which explains the newish look of the place. It's on the lake and has pretty good spots for photo ops. So if you happen to be in the area with nothing to do, why not buy a ticket and have a gander? 15 RMB at the door.
Take bus K4, K12, and 30 getting off at the Qian Wang Ci station 钱王祠站