Good stuff. Finding a Master System inspired OST out there is quite a treat. I enjoyed the few tracks provided, the Menu theme was especially great, the main melody and general vibe reminded me a lot of Shovel Knight. A lot of tunes have this heroic, adventurous overtone to them that I liked.
I'm not sure which to pick between Desert and Menu as my favourite, I'd probably go with Desert for the drums and melody alone.
The one thing I didn't like much about the soundtrack was the reverb effect added to the instruments. I prefer retro-inspired ditties with a more dry sound to them... But it's just personal preference. I also thought the village theme sounded a bit empty, but that might be due to time constraints.
The art provided is what immediately attracted me towards this submission, it's extremely charming and endearing, I hope you do more of it in the future.
Overall, I'd say it was a great soundtrack with room for improvement. The stuff that's there is great and I'd honestly listen to it in my own free time outside of jam constraints.
Hope you have a good shave and haircut!