Very much so! They add a ton of content to an already pretty content-rich game, and after you have them, you'll barely notice they weren't part of the base game before, except maybe the Castlevania one because of the obvious difference in theme. Still, lots of quality content that adds tons of variety to your runs!
While not necessarily retro, I'd add that the modernly available Shadowrun games are VERY good, although they're more cyberpunk fantasy than reaaaaally urban fantasy.
Heroes of Might and Magic 3 is one that instantly comes to mind. It surprisingly still has a very active competitive playerbase, mostly comprised of slavs that have been playing it since they could read words on a computer screen.
Another one that I've personally can't stop playing, is the first Warhammer 40K:Dawn of War game with it's expansions and mods. It's just so good, and I wish a modern version with a modern engine could be made. I don't trust Relic to do that tho.
Other than that, there's a myriad of old console and arcade games that are still excellent. Super Metroid, SEGA Rally, shmups like Dodonpachi and Mushihimesama, Street Fighter 3: 3rd Strike... there are really way too many to count.
I've never played Total Annihilation or Supreme COmmander back in the day. This game is so amazing that it makes me sad that I never did. But the good thing is, I can enjoy it right now. It's still technically in beta, but it's already a complete game that you can enjoy, and I strongly recommend you do.
Very much so! They add a ton of content to an already pretty content-rich game, and after you have them, you'll barely notice they weren't part of the base game before, except maybe the Castlevania one because of the obvious difference in theme. Still, lots of quality content that adds tons of variety to your runs!