End Game Raiding

Currently in the market for a game with decent end game raiding similar to the system wow uses. I don't care if its P2P/F2P/B2P. It needs to be some what populated though, not something thats dying. Im currently playing WoW but mainly pvp, and I can't seem to get back into the pve scene because Im so behind on gear, not to mention I hate how the made it so you have to grind rep to get the gear that in previous expansions would have been obtainable through heroics and JP. Anyways, i've played about everything there is, but never to end game. All I want is a game that has 10/25/40 man raids (does have to be specificly those sizes, just something bigger then a 5man.) and has high pop servers. Thanks!