Yeah, I think some of the bosses will be mid bosses. Course some of the information did say that some bosses will team up and fight agaisnt Travis/Shinobu (I don't know if you will fight a ranked assasin with shinobu or not, but it could be possible). It would be funny if one of the boss fights did happen to be...
"Team 15 Midget Brothers That Fight Exactly The Same",
...at the same time of course.
I hope there isn't a repetative routine like in the first No More Heroes. You know, go do some odd-job mini-games or small assasin jobs to get money, so you could pay for the next match and then progress through the game. Regardless I still liked the game and still play it every now and then.
Nonetheless, I'm still going to buy/reserve the game, cause I love me some NMH.