This will all depend entirely on the club you train at and what your instructor is like. It will also depend on how much effort you are willing to put in, and how much reading and thinking you do for yourself.
As far as the weight training goes - being stronger acts as a multplier for your techniques - one depends on the other.
Self-defence wise, it depends on whether your club will merely teach competition fightng and try and say "this will work in the street". I consider myself very lucky in having an instructor who teaches us with the core focus on self-defence: pre-emptive strikes, and such like, rather than pretending that sports-type competition training will be applicable in a real-world situation.
Visit some of the clubs you are thinking of joining and see exactly what it is you will be learning.