I agree all thoses people making bushes and leaves invisible, and making all range projectile pinky color (while also making them slightly bigger) are definitely cheaters.
Thing is, nothing has been done about that since ages, and i know some other people are starting to fall in the dark side, and using them too.
I'm an archer, and i have great difficulty aiming at long-range, since i just can't SEE my arrow any more...
But i feel more and more people are using thoses "cheats" to make their arrows and bolts easier to see... You may have the "feeling" for archery, but when you don't see your arrow, you don't know if you should aim higher or lower...
Definitely cheating in my opinion. As much as using a controller, wich is a bannable offense, if i remember correctly. All in all, all extra things not provided in the normal mod, giving advantages over others, are cheats.