Looking for some travel advice re: trip after Christmas

The gf and I are going to be in Las Vegas Dec 30-Jan 2. We are both off work from Christmas Day through Jan 2. I'm looking for some travel ideas for Dec 26-30, preferably out west so it will be an easy hop to LV on the 30th.

I've started looking at skiing in SLC or Tahoe, possibly visit Napa Valley, or maybe San Diego or LA. Other than skiing, the Winter weather really limits outdoor activities. We are both active, and would like to see new things. I've been to LA, and it's not high on my list to go back.

We have a budget, not a fixed number, but I'm trying to keep the whole trip around $4000, so after Vegas that leaves around $1500-$2000 for the extra flights, lodging, and activites leading up to the 30th.

Any help from you guys on some ideas is appreciated!