As mentioned in the respective topic, I to would like to see hanako again, especially now as it would plotwise be fitting.
Well Technically she was a powerful Demon lord 10 years after Disgaea 2 and D2 probably takes place quite a while later (seeing the age difference of the far slower aging cast), and it was hinted that Hanako left Laharls netherworld becoming a travelling fighter, but still it would be some kind of a fit.
Also, while neither plot-, nor character wise It's my favourite part, at least both points are original, I was very dissapointed with Disgaea 3, due to the similarities to Disgaea 1 (traumatised orphan crownprince with aversion against love and friendship, with support of a good natured friend and a loyal follower of the late overlord, who still hangs about in the world of mortals, going against a self-righteous crusader)
Since Disgaea 4 proved superior character and gameplaywise (not plotwise I think), to Disgaea 2 the later is now only my 3rd favourite, but I think it will be able to defend the position against D2.
IMHO DLC are a part of game ripped off to take extra money from players for selling it. I not buy it no matter how good or cheap it is. It is matter of principles.
I certainly agree and support that notion but I have to say, that in the PS Vita version, the PS3 DLC content is available from the beginning, without having to be bought or downloaded, making that version a definite non rip off.