Though I cannot recommend any DLC for this game at thier current price (which has not dropped in the last 3 years, might I add.), I can at least say there are worse ways to spend your money. Like The Sims 3: Island Paradise, for example.
It does add a bit of role-playing content to the game, and the new town is pretty decent. However I cannot stress enough that you are better off waiting for EA to not Challenge Everything when it comes to outlandish DLC prices for a now aging game. Let me list 15 ways you could better spend your $20:
1. New backpack for college.
2. Paying part of your cellphone bill.
3. A healthy meal of vegetable stirfry for your whole family.
4. A new hat.
5. 8 packs of Skittles.
6. 17 Iced Coffees from McDonalds this summer.
7. Avatar: The Last Airbender Book 1: Water and Book 2: Earth Complete DvD set.
8. Whiskis Temptations.
9. Whiskis Temptations for the guy that ives in the apartment 3 doors down. (He doesn't have a cat, but he's always borrowing a few spares.)
10. A bottle of wine to share with your old lady.
11. Tomb Raider Reboot.
12. Fund a Nicolas Cage freak-out montage.
13. A different new hat.
14. The Elder Scrolls V: Skyrim.
15. That 1-year anniversary present you forgot to get. (I think Rexall is open; better go quick.)