some of this is just rpgmaker 2000 tiles you aint slick
i think you meant to say this:
"some times in `rpg_tiles.png`, specifically these ones
look like rpgmaker 2000 tiles"
in which case you're right, they have the same structure, and the wooden plank one in particular is just a visually cleaner edit of such a tileset. the others are just a result of using tiles i already made and putting them into that same rpgmaker tile orientation (3x4; 3x3 of border grass, inner dirt, etc; 1x3 tiles above)
correct me if i'm wrong
fair, i heavily referenced and edited an rpgmaker tileset (among many others) to know what to include and for inspiration. it seems the ascending stairs, bed, tombstone, the crates of produce, the rectangular table, little chairs, and some others aren't differentiated enough
i went through and picked tiles from what i saw in both mine and the rpgmaker tilesets, then went and looked at various zelda and final fantasy tilesets for making comparisons. the descending stairs and water well you just shared don't seem bad. i would argue the descending stairs from final fantasy more resemble rpgmaker's. the bookcases and table also seems to be heavily inspired from zelda.
not too bad, i expected much worse of my past self, there is still plenty of other wholly original or sufficiently differentiated tiles. if you see anything else that's obvious let me know and i'll remove it