Jiu jitsu and thai kickboxing sounds like a great combination to me. Very strong, practical kicking techniques along with Western style boxing, plus good, solid grappling and ground techniques.
Most street fights are not boxing matches. They might start out that way, but they usually they turn into wrestling matches pretty quickly. I don't like anyone close enough to me to grab me, but if they do, grappling is the way to go.
Anybody remember when the UFC first started? Royce Gracie was a little guy compared to most of the hulks he was fighting, but he kicked all their asses until they got smart and started learning jiu jitsu, too.