Yea, the visuals need a lot of work, but mostly on the color department. I'm not criticizing your modelling skills. The background is really overwhelming and everything seems to drown into it. Everything is the same orange/brown shades, and that's considered bad visual design. Try seperating the important stuff (player, enemies, items etc) from the background by giving them distinctive colors. Also try toning down the contrast. More contrast = more strain on eyes, most of the time. Try rendering those objects without textures at first and make them work just as shaded, colored polygons. Then see if you really need the textures.