the only reason i could see Jabba meeting with Han himself is to maybe strike some fear into him...
have you seen the movie Scarface? i bring this up because when Tony Montana starts to hit it big he has his hired goons who do things for him which u have mentioned in your blog... but when he goes to confront his friend who ended up betraying Tony and hired someone to kill him.... he goes with his goons to pay him a visit personally... (i sure hope you remember the part in the movie or have seen the movie... he comes in with his arm in a sling... in the room with the palm trees and sunset painted walls)
he still has his goons with him but he shows up as well... maybe to put a shit scare into the guy...
thats the only other reason why i could that happening...
what do you think?