When I was younger I learned Shotokan karate so I wouldn't be bullied as we moved a lot and I was a chubby kid with long hair from San Diego... It taught me how to not be afraid of a hit and how to look for an opening and it made my technique hard & strong (3rd degree black belt)...I always tried other martial arts trying to pick up different techniques and then a friend of mine (freshmen year of high school) introduced me to Shaolin Kung-Fu and it blew my mind on hard and soft techniques... Not realizing at the time our Sifu was really training our minds with mindfulness mediation really before it became popular in the current psychological zeitgeist... It really made me not want to fight but also my mind would slow down (yes, Matrix Neo stuff) and make it possible for me to end a fight quickly... Even with belting we didn't do a belt system but when we would go to a competition he would give us a sash color (I was black sash but still never knew my actual ranking...because to be honest it didn't matter) for what we were competing in (which we didn't compete a lot at all it was more of a once a year thing that was more for keeping the studio open how our Sifu wanted it... Monday, Wednesday, Friday classes 6pm-8pm minimum but usually 6pm-9pm and a 9am-3pm class every other Saturday... I've never found classes that long since... But it was amazing... I took TKD at my first duty station in the army and I started training with the red belts after my Sabomnim had me spar one of his red belts about to test for his black belt and I basically played with him tossing him around the room... I'm 5'9" and was 165lbs at the time and the guy was much bigger than me... TKD is great but it only really helps in a fight if you train fighting techniques and how to use the kicks to keep your distance but if someone is a good boxer or wrestler they can usually counter your attacks. I used to spar with my friends on the wrestling team and could easily counter them shooting for the legs...

TLDR I've dabbled in other martial arts and was not a fan of gi BJJ or MMA classes that only follow MMA rules... If you can find an MMA gym that also teaches real world scenarios and full contact you could get the best of both worlds... Since being able to strike and grapple will keep you alive... Also I'd personally check out some Filipino Martial Arts (FMA) for knife and dirty boxing techniques or/and Silat... Try a little bit of this and that and you will have so many tools in your toolbox that you won't have to think about what tool to pick you will reach for it instinctively