I might be overlooking something, but I don’t see the point of moving the DB25 from the current input section to a new card. Hmmm

As for a new card expanding the number of inputs, surely there are people who would appreciate that. For such a card to add 8 channels, in consideration of the horizontal space available, it probably would have to have a DB25 connector. 

Another card could offer a fewer number of XLR/TSR inputs. Those could either add channels or be alternatives to the existing 8 channels. (UAD’s Apollo x8p has both DB25 and XLR/TSR inputs for the same 8 channels. The user can select in software which is used.)

Offering multiple types of analog input expansion boards would be relevant to the H9000 as a long runner.