Ohai there :P
1&2: Well they barely revealed anything at all yet, it could be that they simply are not allowed to talk about it yet.
3: Well, I don't see how the game couldn't at least read what type of character Charname was, if it would be relevant to the story somehow. Or other variables. I just hope that if they can't implement CHARNAME, that they just don't spe ify who they where instead of replacing them with Abdel Adrian. No one wants Abdel Adrian.
4&5: Meaningful as in is the Bhaalspawn saga only gonna get a throwaway reference at best or are those events actually gonna be important to the narrative. Meaningful: BG2 to BG1. Not meaningful: NWN2 to NWN1. Somewhat meaningful: MotB to NWN2:OC.
6: I absolutely assume that Minsc is gonna appear, he's been WotC's mascot for BG for a while now and their number one Marketing tool to get the BG crowd to try their other products (i.e. Neverwinter MMO). I'd argue that Sarevok has potential for being there as well, since he loses his Bhaal essence but survives either way in ToB. Meaning he didn't have to die (again) for Bhaal to be revived. Wouldn't be surprised either if some of the characters from LoBG would make an appearance either, such as Minsc's new friends. Would love to see Edwin(a) getting a cameo

(And as a wizard he/she could have easily lived that long.)
7. I do hope so, it's kind of a trademark of the series. But I guess it depends on how character creation works.