So, I want to do some martial arts, for self defense. Ideally one that will be useful without giving me CTE, or any long term bad stuff, even though I feel this is already asking for too much 
I don't live in the U๐๐ so gun related stuff isn't really an option.
I'm somewhat heavy, with a year of experience in lifting, and my cardio is not the best, but I can do long walks (of 1 or 2 hours) before getting tired.
I'm going to move to a bigger city in September, and there's a lot of stuff available, so you can comment on the more niche options.
So yeah, any advice from your experiences is welcome lol
If I had known people started arguing over my post I wouldn't have made it.
I've been a victim of random street violence and while I sometimes think about what would have happened if I had punched my way out while it was still a 1v1 scenario, I can't imagine wanting to shoot my assailants.
A friend I worked with would constantly get agitated about how people at the job were about to start fights with him, and he often talked about his pistol being a deterrent. Neither of us is an intimidating presence physically. I only had 1 time when I was afraid of someone being violent to me, and I wouldn't have wanted to escalate beyond a small blade to defensively slash and then run away. Luckily it didn't come to that, because I'm likeable and persuasive enough.
Small blades are literally less effective for self defense than your hands.
Thanks, I'll keep that in mind in case fortune delivers another "situation" to me.
Just to be clear, the reason is you need to do structural damage to stop an attack. Breaking joints or bones, damaging organs, etc. A small blade is going to make an attacker bleed and it's pretty likely to kill them... but only like an hour later after they've already done whatever they were planning to do.