Here's the problem with all this GRF editing crap. You cant always trust the players. How would I know you aren't dabbling in the illegal stuff that was posted. I can't monitor what you do and that's expected. But now anyone can make changes they want and claim it to be "legal" because they just want to see it that way.
Keep doing your edits and share it with your guild members. Totally not an unfair advantage at all.
Same goes for literally every sort of cheat. And it's not unfair seeing as everyone has access to their GRF file and access to the internet to see how to do it. That's how I learned to use the GRF, so everyone else can too if they want to put the edits in. I don't give my members edits unless I ask Campitor and he says they are alright to use.
GRF edits like greymap and nodelay are unacceptable though because they offer massive advantage to a player. No matter what a player does, there is no other way to have xray vision through the walls of the game or being able to spam skills faster than anyone else could humanly do. Seeing a number that you could also be counting in your head is helpful, but not game-breaking.