Off the top of my head, Chuck Liddell, Frank Mir, and Yuki Kondo originally came from Kempo backgrounds, although they expanded for MMA. Chuck in his prime was probably one of the hardest guys in MMA to keep or get on the ground. Yuki just has a ton of MMA fights. You'll get some good striking practice, and can pull the practical stuff out of Kempo. Good old fashioned boxing is probably the best hand striking like @NoKimberDave likes, even if they don't focus on more vulnerability for other situations. Always good to work on the hands. The Japanesse Jujutsu, (your spelling it like a Brazilian ha-ha) should give you some experience with practical throws, takedowns and td defense, joint locks and chokes if grounded, and attacks to vulnerable areas and some practical striking which you don't get as much of in BJJ. You'll have a good base for self defense..........much better than nothing. It's addictive. Can be costly......lol.....dental work is expensive as are brakes and sprains! I've had all 3 in the past. I don't train like that anymore, family depends on me working LOL I really don't know of any Martail Arts I don't like, all have there place. Some may be more practical in today's world.