Four bladed Bf109? Like this?

They did make them, or rather the Spanish did under license as HA-1112s
Accuracy and historical detail are interesting points to consider.
Most aircraft nuts prize those two things above everything else. But, it really depends on what you want out of your art and what kind of audience you want to attract. Personally, I love the research, the planes and their history are what I'm most interested in. But there's nothing wrong with flights of fancy, no pun intended, either

Shark mouths on Mig 17s with WW2 Luftwaffe camouflage might be really fun for a change

Doing something the way you want is what counts most. You could add 4 bladed props onto a purple 109s and get away with it in my book....oh, they made those too
Nice screens Billy