Martial Arts advice

You have a good point about the boxing, but imo it's a pretty aggresive martial art.

Getting into a fist fight can go any which way, and people can get seriously hurt.

What I want is to be able to take someones attack do some fresh moves and end up with them on their knees yelping with me holding their little finger behind their head, telling them to calm down... or something along those lines.

Unless you're thinking about doing Tai Chi then all martial arts are aggressive but boxing isn't just about belting people around the ring... ok it mostly is. I boxed at Angel ABC for a few years and out of all the combat sports I've done over the years (inc Muay Thai, Shaolin Kung Fu) I found it the most satisfying and rewarding and certainly the best for fitness. In terms of self-defence, boxing and Thai are probably the best for close encounters of a nightclub/dark alley kind.

If this post seems a bit testosterone-fuelled, let me assure you that I'm no taller than Pistinator and a bit fat these days.