I agree with everything you all said but I also see him as the nerd that everyone pick on growing up then he became the CEO of a company and could pay a little of that bully back. I don’t think he is crazy but he acts that way to keep anyone from get to close because they might see the kid that everyone pick on underneath. This for Rumple side of him. Mr. Gold side, I see him as Scrooge before the spirits came to visit.
Now Regina and Mr. Gold relationship is very complicated. Which is the same for the EQ and Rumple. I believe he keeps getting in her way. He in away is a balance to her. He is able to get his hands dirty to keep her from taking over FTL because the heros have to be honest and fair. A perfect example of this is when Emma told everyone what Mr. Gold did when she was running for Sheriff. Every good guy needs to have that one person do the things that no else is willing to do.
In a way, Rumple got in her way again with telling Snow and Charming their daughter is the only one who can save them. Which put them in action to try to stop EQ, which lead to the cabinet being built and Emma being sent in the real world instead of SB. He foiled her plans again by bring Henry to SB which leads to Emma coming there too. I also believe that he was the one who gave MM the book and then Henry getting it. Regina also has to give anything he wants if he says “please”. The only thing she has over him is Belle. I really don’t know how powerful that really is because right now he still won’t give up the power and how do we not know he doesn’t know about Belle being in the hospital psyc ward, that could be the favor he ask for from Emma is to get her out when the time comes. It is just what I have floating around in my head but I probable have it all wrong.