I would not want to ski bum in Colorado. The Sierra are steeper and have historically gotten more snow.
I did my ski bum years in Squaw Valley and absolutely loved it. The party scene is fun, for a ski town, but the female ratio is terrible. It is probably better there than at most places, but don't expect it to be like college, as ski town ratios are not good. The women in Tahoe were not nearly as hot as the girls where I went to college and there were not nearly as many of them. Just trying to prepare you so you are not shocked. There are lots of women from the bay who come in on the weekends, but you will probably be working weekends, I usually was. Having said all of that Tahoe City had a fun party scene, just don't expect as many women as you are used to coming from college.
I would not base where you ski bum on parties and girls. If you leave and go to the working world and live in a big city you will find a much better social scene with more and hotter women. You are doing this year to ski as much as possible and get a nice 120 day year. If you leave for the real world this will be your only chance to do this. You should really make this year about skiing and focus almost only on that. I'm not saying you can't party, but you have plenty of time to party and do so in places where the partying is better. This year should be about the best skiing you can possibly get.