simpel mind

to bring in my 50 cent about a BGIII :
a sequel to ToB: well, even in ToB the inflation of items (simple soldiers, wearing +2 cand +3 weaponry and armour) was quite annoying/ boring to me (not even counting the main story -In my opinion (A)Melyssan) is still counting to the three most annoying villains i know).
And remeber the power, even a mortal PC controls at the end of ToB:
What challenges could a 20+ -level character face whithout getting bored??
OK, Ordinary soldiers with +7 weapons and armoury... .

In contrast there are many open questions about the events before BG: Why did Gorion became the PC´s fosterfather? How did he meet Jaheira and Khalid (Yup, I like K-K-Khalid)? How did Khalid and Jaheira meet each other? Is Sarevok (whom I favor to the typical mad-scientist) your real brother? What is Elminster´s part of all these things? ... and many more Questions.
There are so many characters in BG1 and BGG2, who were old enough to face (and survive) the time of sorrows (Perhaps explaining, why Xan is SO depressed...).
The only thing i an concerned, is, that none of these things would be realized in a prequel... (Shudders about the thougth of a Diablo-like BG ... )