Yeah, I let it test by my brother on his old GBA and he said that he couldn't barely see a thing due to the screen almost haven't any contrast left. Another friend of mine had a much better device where it looks quite good. But yeah,...I definitively need to have a real device... but as you said, you played it on a NDS,...I actually do have one(somewhere), that doesn't detect NDS-Cartridges anymore, but maybe GBA works... good hint. Let's find a GBA SD-Card cartridge.
And yes, GBA is such a fun platform to work with. Love it and only scratched the surface. Had to resist to start with affine transformations and such,... 😉
I agree that the dungeons in comparison to the outside world are dull. It was in the end a question of time. Even though it wouldn't have taken too much time to polish this more as well, but there were a lot of fires 🔥 to put out and I gave this the lowest priority 😉
Thanks for playing and testing it on the device(s). 👍