mmmm lets see....
Clipless option for the small Seb at least (ditto stjames & MVG) w/o the cutout
Damascus Umnumzaan
Rotating damascus options (maybe Nicholas or Damasteel options)
Swedge available on the 21 blade
A factory option for G10 or Carbon Fiber on the non-locking Slab
Upgrade Steel option - S90V, CTS-20CP, etc.
Stonewashed plain scales
That's about it for now. Oh, and I'm still dreaming for Chris to make some custom, hand-made Seb's or Umnumzaan's in the spirit of Rick Hinderer, Ernie Emerson, etc., outside of the production line. It won't happen, but I bet he'd sell new "H" models for whatever he wants to ask for them. Who here wouldn't buy one?