I Just Wanted To Suggest That The More You Donate The More Disguises You Should Have Available Like For Example I Have [Extreme] Rank That Was $200 And I Don't Have Permission To Be A Wither Skeleton Just A Though. And Maybe Take Away Or Lower The Refresh Timer For /Wild
I think they made it so that you aren't able to spawn as a Wither for a reason. It's very abusive. I'm not saying that you would though. I do agree with you on the /wild timer though. That could be removed, for your rank anyways.