Knowing some striking for self defense is a very good idea, grapplers should learn how to close the distance - or at least keep distance without getting knocked out!
Judo has definitely an egde over BJJ when it comes to second line defence, after bodycontact is established, to throw and keep fighting standing. Being on top if fight goes to the ground will also be of outmost importance, the last place you want to be in a streetfight is on the ground defending from your back.
Thats also my main problem with BJJ for self defense or street fight, wimpy takedown defence, lousy throws and usually ending up on the ground defending from the guard when fighting a physically stronger guy...