Cute visuals! Always love to see more retro RPGs and I think the art style for this is well done. Some of the map layouts and tile placements are a bit weird and there's an odd effect with the water that I don't think fits the aesthetic, but for the most part the graphics are solid. I do wish there were more animations in battles, as other than screen flashes for magic it's all (very fast) text.
Music was OK. I would advise caution using that DQ III overworld tune even for a demo, tbh. The tracks I couldn't identify from other games did vary in quality a bit, but were fine on average.
I think the stat curves are too steep for pretty much everything. It felt like I doubled in power every level (one shotting the intro area mobs at level 2) but going just a bit too far outside of the ideal encounter zone was rough and didn't yield enough xp to feel worth it. Which, when most of what you're doing is farming, doesn't make for a super fun experience. Granted, that focus on the grind is very on par for DQ I, but I don't know if that's one of the design elements from Dragon Quest that you really want to emulate (or if it is, there has to be another way to make it more engaging).
Default controls were a little funky but manageable. I wish you could equip stuff from the Equipment menu rather than just from the Items menu, but I eventually figured it out.
Overall, interested to see where this project goes!