Super! Played a lot, got lucky with this run in the screenshot. First playthrough had feather hat & 2x angelic armor, and whetstone + hatches/shivs. Collected couple Berserker's Rings to sell but never saw another merchant... beat normal game.
Infinite, Lucky Blade found more Berserker's Rings so just went crazy with NO armor. Beat Infinite King, took a lot of mana, but 11 energy + Necronomicon kept it up. Screenshot attached.
Idea: Of course add more story. And make the map a lot bigger, like the current map for each floor could become a smaller "area map", and these areas are all connected on a master "world map", where you can take different directions on the small (current) map to head N/S/W/E to a new area with different classes of enemies, maybe some dead end maps, different routes to take...
[Below comments were also in the hotfix 4 page, fyi]
For item interactions, permanently showing a little overlay saying "+1" (in different colours for different effects) right on the border would be excellent. Figuring out how things like armor and helmets interact can get very confusing, but seeing little +1's and +2's on the borders should hopefully make it much clearer.
Maybe making merchants STAY PUT so you can come back and buy & sell stuff later would be great too? Same for those mystery hallways and statues, they definitely shouldn't be wandering away...?