If I must be frank, the older I get, the harder it is for me to accept Han Solo as a serious character. In the past ten years or so, I have regarded him as a bit of a man child. So a Han Solo movie with heavy humor doesn't seem upsetting to me.
I've always felt that way. I prefer the term though of "lovable rogue" myself. For me I think the humor should come from the banter between Solo and Londo. Chewbacca always is good for a site gag and a reaction shot. Not sure about the newer characters and what they will add.
Things I expect to see is the Kessel Run and the card game were Londo losses the ship to Solo. I guess Jabba will be in it as well and I wouldn't be shocked to see Bubba Fett and someone's got to make fun of the now legendary issue of Han shooting first in some way.
Jason