What games can you recommend that didn't get the appreciation that they deserved?

Obligatory: Roguelike (well, Roguelite but that starts getting into the berlin bullshit). Rogue is a class in tabletop RPGs and a historic game. Rouge is a bunny rabbit in sonic and a kind of makeup.

That aside, here are a few off the top of my head:

• Distance: Mostly a "beat the clock" style racing game in the vein of trackmania, although the synchronous MP with collision is a great time at a party. But it also has a weirdly good singleplayer campaign with both a narrative and some solid mechanics and set pieces. Also a ridiculous steam workshop presence
• Tales of Maj'Eyal probably doesn't belong here as I think it has been ridiculously successful for a game made by a small team and consistently comes up in discussions by anyone who is aware of what "the berlin interpretation" is. But it feels like it is almost completely ignored in the overall cultural zeitgeist when roguelikes/lites comes up. Which is a shame since TOME is very much a roguelike (technically lite, but... meh) with some solid design concepts. The vast majority of runs feel like they were "worth it" and even the early leveling has enough variety and wrenches that it feels less like you lost an hour of your life when you wipe and more like you get to do the Sand Worm again. Some of the unlocks are complete bullshit (although, I want to say the special magic trees were just made "free" because everyone hated it?), but it is generally the kind of game where you can work toward something with every run.
• UFO: Aftermath/Aftershock (fuck Afterlight). Back in the dark ages between Silent Storm (WOOO) and the 2012 nu-XCOM, there were a lot of eurojank games in the genre. And while I don't think UFO Aftermath was "good", I do think it was competent. But mostly? It is probably the best Stargate SG1 game ever made. Because the devs were trying to cash in on that Jagged Alliance craze and made the human weapons stage a lot longer. So you might find yourself in an endgame with a few G36s backing up your plasma rifles as you fend off the obligatory base invasion. Aftershock, and especially Afterlight, lost a lot of this charm (because they are years later timeline wise) but were still fun
• Silent Storm. Sorry, Silent Mother Fucking Storm, if we want to be specific. Alternate history WW2 where you play as a special organization for the Allies or Axis that are investigating a third party who have the potential to turn the war itself and blah blah blah. Mostly it is probably one of the best balanced JA2 style AP-based strategy games out there (just... get a save editor because the leveling/training is broken) with an emphasis on line of sight, trajectories, and full destruction of terrain. The kind of game where you might spend six "turns" getting your scout into position so that you can have your sniper plug a person from behind a wall, your machine gunner unload on people sleeping in a barracks, and your grenadier to... make the guard tower not exist anymore. All without ever directly targeting an enemy because you are fully operating based on magic radio commands or whatever. Again, this probably doesn't belong here since anyone who liked JA2 back in the day was talking about this but it more or less fell off the face of the earth in favor of nu-XCOM. And I feel like the genre would be pretty revolutionized if people remembered this existed.