Tae Kwon Do, traditional complete Japanese ryu, some Aikido.
You can see in the traditional Japanese styles where Aikido techniques were derived. But where Aikido lets them down mussed or bruised, the traditional jujutsu breaks and tears.
Had a man tell me once that Brazilian jujutsu is the best one on one unarmed system in the world. I pondered and told him,"That might be so but it leaves you with two problems: finding me alone and finding me unarmed."
The old Japanese styles seem sort of strange to someone who is schooled in modern hard styles. Many of the strikes and kicks seem to be weak, short ranged, and less than the most effective. And they are, in fact, exactly that. Until you realize that the focus is totally different. The focus is fighting multiple opponents. Strong techniques that leave you off balance and out of position for the other opponents to strike are avoided in favor of sneaky crap that will get the target off balance for your associates to hammer.
There was a lot of work with improvised weapons. You've got the knife? Fine, I'll take a garden rake. Or a bat and a trash can lid. Or a shovel.
A study of the use of terrain can be of positive benefit. I've had people chase me into construction sites...to their regret. Don't follow me up a ladder. A loose concrete block and gravity make excellent allies against a stronger and faster opponent.
A study of strategic principles can be enlightening also. Many individual martial arts today boil down to-"hey, diddle diddle, straight up the middle." That's fine if you've got the superior skill, strength, endurance, and speed. Not so good if the other guy has the upper hand in those departments. Having the ability to shield your weaknesses from the opponent's strengths, while using your strengths to engage his weaknesses can go a long way. Another construction site fight-amazing how little his superior strength, speed, endurance,and skill helped after getting mortar mix thrown in his eyes.
About the only way someone will fight me "hand to hand is to attack me in the police station or courthouse or some other criminal safety zone. Even then if I've got a Bic pen, I'll be trying to see how good he can fight after I ram the entire length of that pen into him with the heel of my palm.