Another thing to remember is martial arts are, usually, perishable skills. In other words, if you aren't training regularly the skills tend to fade over time. So if you want to optimise fighting skills, it is going to take a long-term investment and commitment.

Another factor to consider in physical "self defence" training is flight training. Sprint training, running endurance, climbing, parkour etc.... All skills that can be trained.

It amazes me still that people in the martial arts community have often rationalised that training flight skills is either not important or much less important than fight skills. I don't get that. If all you've trained to do is fight and you can't run the length of yourself, you're limiting your "self defence" options right from the get go. I sometimes wonder are such individuals really interested in self-defence or just reacting violently when there may be other avenues available. I'm not saying you can always run away, but if you get the chance and you can't take it because you have awful flight skills, well...
"Let your food be your medicine, and your medicine be your food" Hippocrates.