In your opinion, what makes a good mod?

I think that, like you said, graphics (textures) are important, but probably the thing that makes a mod good is its usefulness.

Would you download a mod that does something that vanilla or many other mods does better or that removes the fun from the game by adding some OP things?

I think that a good mod is one that adds more gameplay, eases some boring tasks or improves some vanilla aspects. And originality also helps.

But it's actually a matter of opinion because every player likes a different part of the game: for example, hardcore players could prefer mods that add new monsters and menaces, while builders might prefer the ones that add new decorative blocks or some utilities to stop the annoying mobs so they can spend more time building.

For me a good mod is a mod that follow the vanilla minecraft, but that's actually just my opinion, in fact I think most people will like a mod that add a fun experience to the game, a fun and long experience, as the aether for exemple :D

Little late on this thread, but personally I believe that what makes a good mod is one that can provide an interesting experience. I don't really enjoy those small mods that add a few things or a few new biomes and ores, what I enjoy is a new experience. Something that completely flips minecraft on its head. Pixelmon is a great example since it takes minecraft and makes it a completely different sub genre. Of course it doesn't have to go that over board, for example several tech mods completely change how you will go about playing minecraft, but be a lot more close to the source material. I enjoy those types of mods because to me the magic of base survival is gone. I've been playing since 2012 and the enjoyment of booting up a survival world lasts for 40 minutes and then I leave and watch youtube or something. I don't think I've ever really been one for games themselves either but creating things is always enjoyable, and I think developing something more gameplay redefining is more fun to make (and difficult). In the end, I believe the bests mods are ones that are not only interesting and different to play, but also fun to make.

Ability to use in survival. Sorry creative guys the majority of people who use mods do it on survival not creative. You have to make it actually useful or just so stupid it’s funny like the Ariana Grande mod. In my jojo mod (idk if you watch but crazy diamond is a spirit type thing that fixes stuff) I am making in next update a way to get it in survival, and crazy diamond fixes your items when you right click. You have Chile pepper that spawns lightning on your shots. Limp Bizkit that spawns 20 zombies where it hits to kill people you don’t like. See where in going here? There’s actual use for it. You gotta make it useful in survival or just so dumb that people would download it.