Those aspeks are proper simples, I don't see much need for improvement except on maybe the cracks, try and make it more flowing.
Tuco, finish that C first, you aren't ready for effects like that. The letters are simple keyboard letters, just keep doing those until you can get your lines smooth and straight, they're pretty wavy, just be confident in your strokes. Also fix the R, there shouldn't be that top bit, it should be uniformly smooth like the other letters.
and angle the diagonal bar at a 45 degree angle and keep it straight, it's slightly curved while the other letters aren't.
Try and work on your parallel lines.(====) some of them don't match up.
Dr Doodoo, the middle phony is the best for sure. stick with that, bottom N needs more space between bars.
Kele, that one in the left corner is the best imo...