Well it mostly depends on what you're looking for, there are 3d games, RPG Maker games, flash games, etc. But if you're looking for something paid with regular updates I would suggest having a look on Patreon, there are many indie developers trying to put their imagination into a sort of reality, however you will only find western games not japanese. You can also get free demo versions to test the product before paying for it, that's a big upside if you ask me.
I was just about to say the same. There's also the VN/RPG Desire Dungeon, which has a full translation as well. Kyrieru's two platformers are fun and cheap. MoGi: Origins, another platformer, is unfinished, but looks good so far. It's a little expensive for my tastes, though.