I just completed The Antagonist. I really like it! This post will contains spoilers.
The gameplay is the main attraction here, and it is a lot of fun. The lack of mission objective diversity (destroy enemies, survive) is not an issue, as there are some interesting gameplay mechanics that I haven't seen before, and a wide range of cleverly designed enemy ships and weapons. There are balance issues; some player weapons are rarely useful, and the final missions (near the star) were disappointingly easy (possibly due to the overpowered low-cooldown Zwide SSM).
There are a lot of novel ideas in this campaign, particularly with regards to jumping in and out of subspace to fight enemies; unfortunately, the execution is buggy (probably due to engine limitations). For example, when entering normalspace, subspace missiles are still visible and still collide with the player. Also, if the player warps to subspace while another ship is in the process of warping out from normalspace, that other ship will still be visible disappearing into a portal from subspace.
The boss fights are an excellent idea. Each boss personality of their own and a unique battle strategy. However, the Ozmund boss fight is too rigidly scripted, and the FREDding is transparent. The mission will not allow the player to cause more than 25% to the shield generator at a time. It is obvious that it is a different ship every time it warps. This breaks the illusion that the player is chasing the quarry between dimensions. It would be great if there were more ways of fighting this boss than by following Edward's commands (such as simply depleting the shields by force) and if damage done carried over between jumps.
I like the quirky setting, with its caricature villains. The player gets the impression that they are all alone in a hostile world, at the helm of an extremely advanced machine; powerful, yet vulnerable. The voice acting is a nice touch; it's not convincing, but it is better than silence, and it works fine for the cartoony tone of the campaign. I'd like a plot hole filled: why would anyone in the Oligarchy program Edward with his mission? Also, why does the Oligarchy have a navy?
Stylisitcally, the ship designs are well chosen, and the music is unintrusive. The ABE cannon really needs a better sound effect; also, the giant flash it makes seems disproportionate to the damage it causes.
The game crashes from time to time; I haven't noticed a particular trigger.
In conclusion, while this campaign lacks polish in some areas, it is a lot of fun to play. I would welcome an update that fixes issues, and I am looking forward to Bigchunk's future works.