Depends on the property, and what status you can obtain.

If you can manage a Gold Challenge, it's worth doing if you'll be able to make use of lounge access at FS Marriott properties (the one in Victoria, BC is particularly nice )

I've had no trouble with guesting my wife and daughter in to lounges, but I believe it's supposed to be just 1 guest although it seems discretion is applied if you're travelling with family. YMMV.

With our crappy petrodollar exchange rate, you'll get more bang for your buck with international hotels. I'm just looking at TPA hotels for the night before we fly home, 25k (or burn a Cat 1-5 certificate) seems to be good value, make that great value if I use the lounge for dinner and breakfast.

Travel packages could work well if you can get enough points amassed to do it.

Good luck!