Traditional Roguelikes, so turn-based. I think an important part of roguelikes is the concept so some of these I'm bumping descriptions for solely because they got an interesting one:
Brogue - free and good. Play it as long as you want. If it 'hooks' you then you basically get a great game for nada.
ADOM. Never could get into it. Also free or paid, up to you. Has a lot of depth and apparently never even been beaten by the guy who made it.
Tales of Maj'eyal. The "Diablo 2" of roguelikes, IMO. Lots of itemization and what not. My main problem is I get very tired of the same areas/lack of procedural world content.
AliensRL, DoomRL, and Jupiter Hell. Free, free, paid. All made by the same bloke, each one iterating on the last. I think Jupiter Hell is the best of them. Very refined, and gets better with every update. LOTS of builds. Very action-focused, but the harder difficulties will kick you in the nuts.
Caves of Qud. Best setting, IMO. Best character creation. You can make anything from a gunslinger to a four-armed superhero. Lots of depth. Aesthetics are top tier if you're into dreamlike low-fantasy/low-scifi. Has a story mode of sorts where you can follow the main tale -- or you can just mosey around doing whatever and exploring wherever. Best all-around roguelike, IMO.
Cogmind. Like Caves of Qud, but with robots. Been awhile since I've played, but a few things: large build diversity, very strange robot-type setting, and a very impressive graphic set for what it is. You're basically a sentient bot and you make yourself into a swiss-army knife of other bot-parts.
Golden Krone Hotel. A solid roguelike. Uses a light/dark dynamic. I kinda wish it was a little more coherent. I still play it now and again anyway.
Approaching Infinity. Scifi roguelike. Part of the game is you on the ship running around solar systems. The other part is your away team going down to planets. It's pretty great, but my main issue is that it doesn't get 'interesting' until about 10-ish solar systems into the map. The concept is fucking amazing though if you're into that Star Trek type vibe.
Rift Wizard. Combat focused spellcasting roguelike. Very difficult. You're a wizard and you can basically dip your toes into a zillion spellcasting schools. Great concept.
Curse of Yendor. Simple roguelike, fun to play, a little depth under the hood. Made by the Approaching Infinity guy.
Xenomarine. Another ranged-focused roguelike. Somewhat difficult. I particularly liked this Roguelike and I'm not sure why. Something about it drew me in and I'm apparently one of a handful of people to actually bother beating it. Aliens aesthetic is very underused in roguelikes so that might be why.
Sword of the Stars: The Pit. I actually don't understand how this game manifested out of the SOTS series, but it's a solid roguelike with a scifi/aliens styled concept. Very difficult, IMO, but part of that is due to some annoying design decisions moreso than strictly the gameplay.
Shiren the Wanderer. GOAT-tier mystery dungeon game which is in essence a roguelike with persistent stuff going on -- but you are in control of what "persists" which is why I didn't X it out. So it somewhat fits in your category. Main problem is it doesn't get particularly hard until a few hours in, and then it nukes you repeatedly and without hesitation. The type of Roguelike where your badass samurai sword of doom gets turned into a rice cake.
Armored Commander games. Roguelikes where you control a ... tank. Strange, but unique concept. I have the 2nd but haven't yet delved into it.
Cheapo fastpaced Roguelikes that are solid but do nothing outstanding: Dungeonmans, Rogue Empire, Rogue Fable III, Mainframe Defenders, Crown Trick, Haque, Dungeons of Dredmor.