Three is an ever-green game. It requires more strategy and planning than 2048. I still play it, over five years since I bought it. Easily worth the $6 to purchase.
If either of you (or others who like Threes) have an iOS device, check out SPL-T. It’s similarly engaging, and completely deterministic. Which means you have no one to blame but yourself for losing. Someone who’s really into math might be able to solve it and play forever.