I feel like the Antagonists objective is to do just that, Antagonize. They are there to "ruin their day" not necessarily 'win' so if you slow them down, lower their respawn pool or the best possible scenario, make them pay for Aleph? I'd say they've successfully completed that objective and should get excellent rewards for doing so. I'm talking, 10k faction pounts, 15k gold or the choice of TWO bp's.
I'd be way more inclined to play antag, die a lot but ruin their mission and get great reward from it.
As it stands, I will never EVER play Antag.