Odd but this seems to be appropriately off topic. There are games, but not the way we want there to be games. There have been some really neat games, but they are history. There are some cool things going on on shared servers, but...
A lot of work has gone into setting things up to make games, but a neat tool for building worlds has almost gotten stuck in the building of worlds. Part of this is because we have a guy named Sam that is able to do everything. Most of our games are odd transformations of the base game. You start out standing on a chest in the middle of an endless sea. That sort of thing. Really good, it adds a new twist of learning, but learning the obscure irrational way of a new world is both interesting and meh. So enough with complaint, here are a few thoughts on what to do to give the game more depth.
I think a game like mario cart is possible and would be amazing. I think with just a touch of work, this game is ready to be a great first person shooter.
This game could be made into a classic old style RPG with just a few odd mods. If, when a monster was encountered, it switched to a mini arena and combat with the team that Sam had put together fighting a group of monsters, a rather classic adventure game could be enabled. None of these games would need to be exclusive from the normal mine and build scenario. Another thing we could do is increase the playabilty of the base game.
We could make the layer of ability easier to control by settings. Right now we have Creative and Enable Damage as the two flags. This is a great environment for building and testing a game. I like the mining game, but I think, in a way, it limits some of the dimensions of the game by setting Sam outside of the need for community or goals apart from building. It is not that Sam has it easy, it is just that he has an easy way out of his needs and no need for anyone else.
Right now the game is sort of done in six or so hours. Sam needs to find apples, dig till he gets mese and/or diamond, find a jungle so he can plant cotton and somewhere on the way find a rose so he can make a bed. Complex mods add the ability to make fancier buildings and sets, but eventually that wears down and starting over is more fun than continuing. After you have a nice building or five, a few roads and a nice garden, it is time to take a break and then start over.
Sam needs someone to rescue. He needs an enemy. Odd as this seems, he needs a griefer to give him meaning. If the menu had another flag and Sam needed to apprentice himself to learn to do things, it would be an interesting addition. If you had to do three favors for the fellow you want to teach you something, it could add several hours of fun. Missions can be things that you don't have to complete. Completion would be rewarded though. if you want to refine iron instead of buy it, you will need to go on a few errands.
These are a few ruminations on what I think are the low hanging fruit that could be easily picked to make a more playable environment. Minetest has amazing potential. It is an amazing game engine waiting for an amazing game.