My 2 cents:
what I like
-contrary to a lot of users, I really like the handle size and ergs (maybe its just my hands)
-blade size
-compression lock
what I'd like to see
-tip up carry
-deeper pocket clip
And finally, something that separates the para from the rest of the Spydie pack: not just CF, coloured handles, etc.. although these are all great comments.
I think something that hasnt been done by Spyderco yet or hasnt been done in a while, would be good for the paramil... like ppl have suggested: possibly a different steel or rare handle material
However, it is my EDC so I may be a little biased.