For me - not a totally flat seat but not a really deep one either. My current saddle is possibly a tad too deep. The panels as wide and flat as possible and specifically for Jenny as wide a gullet as possible. For the flaps a nice banana shaped knee roll with poss a slightly bigger block at the top. Maybe a thigh block but so long as the knee block was sufficient I'm not sure I would need the thigh block.
Personally I don't like jumping saddles that have very short tree points - supposedly to allow more room for the shoulders to come up - I've never seen one that doesn't lift up at the back as a consequence.
be careful with very forward cut saddles in case it impinges on your horse's shoulder movement.
knee/thigh rolls are all a matter of preference. i would suggest a mid to flatter seat as a really deep one doesn't always allow you to release your seat properly.
happy jumping.
p.s.
I know of a henri de rivel event saddle looking for a new home.