I know most of the Bethesda RPGs have massive mod support, and there's games like Minecraft that have more mods than anyone can imagine. I would consider those games pretty playable in their vanilla states. Would you say there are any games that were "saved" by modding? Or that are still kept alive by thriving modding communities? What are some of your favorite mods?
I have spent many happy hours playing GW2 and ESO. Mods have improved the GW2 experience significantly, but the game is still playable without them, if somewhat annoying. ESO is completely unplayable without lots and lots of mods, at least for me. I'm so directionally challenged that I gotta have my minimap.
It's been a while since I played, but I remember BlishHUD being really useful. It's kind of a Swiss army knife, with all kinds of helpful options, like pathing, instructions for dailies, and so much more. Looks like they're still active.
https://blishhud.com/
Somehow it almost never occurs to me to mod multiplayer games like that, even though I suppose interface/UI mods must usually be workable. I know Don't Starve Together has some good ones.