I've been holding this back for a while, so I might as well let you guys in on a little secret about my what little wolf3d designing capabilities I may have.
I'm no sprite designer by any means because I don't make mine from scratch and they are not really unique. However, in the past, I have made sprites for my own personal use by either modifying them, recoloring them, or in one case trying to copy off of one starting from scratch as much as I could.
Here's the example of one I tried to copy off of. I'll reveal more later depending on your reactions. Feel free to use them in your mods if you wish.