1. During one of the specter's extreme deaths (I believe it's the one where it splits into 4-5 pieces), both red and black blood come out.
2. Blood fountains are still much more common than gibbing and the combination in zombiemen and imps.
3. Footsteps are the same whether running or walking.
1. If possible, tone down those light posts with the lens flairs or make them more natural; they seem to cast light onto any nearby walls in a spherical shape, even those above them.
Spoiler:2. Change the armor back to old armor sprite; it matches the DooM's old sprite style.
3. Remove the distorted/animated water/blood/acid fall flats. They don't look natural since liquids don't wave back and forth while falling.