I think Biss was at his best for Brighton as a 6. Could be wrong though.
In my mind Biss strides through MF shrugging players off helping us break the press and help us up the pitch like a less silky Dembele.... That's the Brighton player I remember.
Him being sat as our deepest MF shielding the defense is a waste IMO; he's more dynamic than that.
Whether Ange will see it that way; I'd have no idea.
Above point remains though; if we're buying yet another DM they need to be able to progress and recycle the ball well.