Muay Thai, Boxing, BJJ, Wrestling, MMA.

All are great and more about getting a better teacher than which discipline is better per se.

If you want to learn true self defense then something like Krav Maga or JKD is a better choice.

Martial Arts wise I think a mix between grappling and striking. E.g. Boxing and wrestling or Muay Thai and BJJ. Or vice versa.

Good luck.

Or piss me off when I've had a few.