I don't think the RFC process is especially onerous. Just slap together a few diffs showing what has been done and the actions you have taken to try to resolve the problem and how the other party has reacted (or not reacted). Get your co-complainant, who has tried and failed to resolve the same problem, to certify with you, along with his own evidence. Move
Easier said than done. Locating your co-complainant is the tricky part. You just won't find many editors on Wikipedia who's first experience of the community was a banning. They tend to leave pretty quickly.
Successful arbitration cases have been brought against administrators, some of them resulting in loss of administrator powers. Usually in such cases there has been consensus amongst other administrators that a particular admin has gone too far.
I think I remember one case in which the ArbCom revoked administrator privilegies from an admin. Some admin who had a name consisting of tree digits and was not 172. But you are talking in pluralis meaning that you have seen more than one instance of this happening. It would very good if you could describe the events so that we can see how far an admin actually can go before he or she loses his or hers privilegies. Set a precedence, formalize the rules, so that it doesn't seem like admins are VIP:s with diplomatic immunity.