Jabba and Boba both provide resource advantage, so the idea is for the deck to basically “out mana” everyone else. Use Jabba to put a bounty on someone, kill it, trigger both Jabba and Boba, cast some more stuff, etc. Over time that advantage should become huge.
There is also a big “Jabba’s Palace” theme with bounty hunters, underworld, etc. Who doesn’t love ROTJ, right?