[noobiess]

Here is my theory in how to obtain momentum:

As reachzero already said, the main idea is to create a pokemon that is a favorable mashup to a pokemon to obtain momentum.
For this i would focus more on speed. One of the worst senario's is that the opponent has a fast sweeper that you wan't counter with any pokemon you have left.
I think we should prevent this to make CAP1 able to make that fast sweeper loose his speed priority and be forced to phase or be killed.
To do this, I suggest making a little-better-then average pokemon who has some good attacking stats that has an ability that creates a trickroom by itself.
Kind of like sand stream,drizzle,... . But actually I prefer to make it only for the pokemon itself. So when the pokemon dies, the trick room also is gone.
Maybe soem people ask why not just make a speedy sweeper... Well I think this pokemon is able the outspeed even pokemon that gained alot of speed because of their ability,moves,... (for example exadrill, agility, blaziken,...). Wich makes him a stong counter-pokemon who really could change momentum :)