Eh, should have went for classical 2d doom style pixelated enemies with reference sprites. I guess you or someone else can draw, so it shouldn't be a problem making pixel art besides maybe programming a bit. 3d models are a heavy load for a single solo dev, unles you have too much free time. Even horror games here on itch as 3d retro games use simple simple animations. One has to understand one can only do so much alone. Ashes 2063 devs made 3d models it seems to make 2d pixelated sprites, so one could also do that.