I agree with you there. HT seems to be pushing a lot of collectors out the door or "pricing them put" so to speak. Myself being one of them. Thats why Ive cut way back on pre-orders, after HULK, Im not even sure if Ill bother pre-ordering any of them any more.
Aside from the DX01 and DX02 have iffy PERS and Indy with the "guyliner" I think all the others have been a home run.
DX03-GREAT
DX04-GREAT
DX06-GREAT
DX07-Not sure yet
DX08-GREAT
DX09-GREAT
DX10-Not sure yet
DX11-Looks great
DX12-Havent gotten in hand yet, but Ive seen pics that make it look goofy AND some that make it look great.
As far as functionality goes I havent had a problem with any of my DXs. Even DX01 and DX02, but I know there has been issues.
EDIT: As for BTTF being a DX, you are probably right, I remember HT stating in an interview back when the DX line debuted, that it was reserved for "Very Iconic Characters" and I think of Marty McFly and BTTF being "Very Iconic" so it probably will be.