I will agree, this topic has been tested before...you're asking for a flame war (hopefully it won't happen, but I am a student of history and history on these forums show us it probably will). That said, I would like to amend a few points:
A highly customizable gun is not neccessary for sniping in PB or in combat by your definition. In combat, an M-16A2 can be used to snipe if the shooter knows what he is doing, and there is nothing customized on it. In paintball, since I don't have a problem seeing the 200 ft that my ball may eventually get to off the hop (I always estimate 100-150 feet for maximum target range), I don't need any special equipment to make that shot. I have a longer barrel, but that is another story...I use it because of my setup and how I shoot.
I can hide with a bright hunter's orange jacket just as well as with camouflage. It depends on how much movement you have to catch your opponent's attention.
Finally: snipers (real snipers) don't use silencers. That is a good old fashioned myth courtesy of Hollywood and the video game industry.
Your intentions are good, and I think you set foot on a good path to argue it, but the diversity here is too great and there are many differing opinions as to what a sniper is. I go by the historical definition of a sniper that has evolved from WWI, but somebody else might go by more of the classical "sharpshooter" aspect (which is anything but a sniper, but that is another thread). I suggest that you play your way and forget what anybody else says. Besides, it sounds like you are convinced of this anyway so what should our opinion matter?
For as I walk through the Valley Of The Shadow Of Death I fear no evil; For I am the Shadow of Death and evil must fear me.
"Get your facts first, and then you can distort them as much as you please." - Mark Twain