Splendor

But Splendor? It's strategic enough, but too short for him to get his stuff optimized, so I end the game quickly winning every time we play 2 person.

Partially related, but my spouse and I found that changing Splendor's nobles from patrons who gave points to tax-collectors who stole points really added a new element. You wanted to do well, but you had these traps to avoid so as not to claim negative points.

I'd remove Catan from any gateway boardgame to be honest. Games where you can be out of the game for a while due to luck will make possible new players sour on games. Splendor (maybe combined with Century: Spice Road) and especially Ticket To Ride are much better entry games.

TtR Europe is a close second behind Rajas because Azul and Splendor are so much better gateway games for us. Targi also fell flat for us but I want to play once or twice more before deciding to cull. * **Best gateway game:** Splendor (by a country mile). We still enjoy playing ourselves, even many years on owning this game, and it's also very easy to teach board game newbies.