After all the new stuff added recently, it would be nice to have some lovely tile sets to go with them. A few areas that come to mind include:
Volcano: The cave setting is fine, but the grey area really doesn't match the theme. I think it should be more red/brown in color to make it more like a volcano.
Fungal Forest: Again, cave is fine, but it's still a boring grey (where in ascii it has a pretty green/yellow/brown color) Maybe having some random mushrooms growing around or giving it a different color would be appropriate
Heavenly Area: Haven't gotten to this area myself, but if it's the same as the other areas (just being grey), hopefully that can be changed to something similar to what ascii has.
I know the next thing being worked on is PC customization, which I'm super excited for. Hopefully an update to the tile sets can also be in the future as well, as I'm sure it would give the graphic version of ADOM some extra flavor.