Expanding more on the small project front, I have played Undertale and Omori and enjoyed both, the first one has pozz up it's ass, but isn't preachy about it (though it is preachy about other things) and I find enjoyable (no, I don't pay attention to the fanbase) and the second one I found entertaining enough and I don't think it had any particular pozz (though the ending can kind of ruin it). I really want to put some time to play Lisa the painful (though that one has zero pozz and I spoilt myself through a lets play, but it seems like a fun romp to experience directly) and have also played Jimmy and the Pulsating Mass (need to grind did sour me at the end, but was a good attempt) and I'm definitely open to any other recommendations of the sort. I'm also keeping an eye on Sea of Stars for example since it looks gorgeous, but of course, I still need to hear the word of mouth once it comes out before I consider going in.
I'll help you out, I liked all the games you listed, so I'll give you some more sort of like them in the RPG Maker arena.
Demon King Chronicle tops the list. It has fairly unique gameplay systems.
Exit Fate is very close behind...
...but play Last Scenario first.
The Way, if you can stand the low-end presentation. Purely for the "what the fuck is going on" story. It's one of those where you have to piece things together from context clues.
OFF. It needs no introduction. Play it.
Re:Kinder is interesting in that it's kind of Earthboundy in one location, but a tad edgier.
End Roll is arguably OMORI's predecessor.
If you can stand possibly the corniest Marty Stu villain in RPG Maker history, I would go with Demon Legacy and Phantom Legacy. It's just so... 90s Internet, for lack of a better term. The villain/antihero just eats the scenery for breakfast. It's just so lame, but in a charming way.
In a similar vein to pure corn, Umbral Souls. Badly needed an editor though.
Weird and Unfortunate Things are Happening is pretty high on the quality scale in a modern setting.
If you like LISA, I would suggest Fear and Hunger. It's quite possibly even more gross and brutal. The sequel, Fear and Hunger 2: Termina, just released. Just don't play it with family or kids nearby.
Hello Charlotte is good, but weird. It has three parts, all are different RPG genres mechanically, and it has a coherent narrative that is OMORI-esque.
The problem with searching RPG Maker games on Steam is a lot of them are porn. Those arec what I can think of that you might like off the top of my head.