So, I've played about a half-hour of the new expansion. SPOILER WARNING.
7/7 Brutal/Mime Vanguard/Mime Dyson 6 Traders Golems 4/10 Spirecraft medium Nomads 10/10 Alt-champ Progress 5/10 Exodian Blade
Avenger on both, Preemption 4 on AI 2.
Notable things: Are all Nomads Mk4? I had a Mk4 Nomad right next to my homeworld at the start.
Also, despite having Preemption 4 on AI 2, no ships seemed to have been freed as threat in the 30 minutes I've played so far as a result. Or, at least, it hasn't shown up on the Threat meter.
The first Brutal mk4 world...well, I found it with...a Wrath Lance, Gravitic Command Station, a Widow Guardpost, a Tractor Guardpost, and a Munitions Boosting guardpost...on a Bunkerer subcommander.
Despite having warp counterattack posts turned off, we found a Rude Gesture subcommander (no warp CP posts). On a Nomad.
With the Dyson Sphere (intensity 6). Hilarity can ensue.
The second Brutal mk4 world we had was at a chokepoint.
With a Core CPA post. Wonderful.
Other things: As I was capping some planets, the Nomad world I captured that was adjacent to my homeworld got cut off from my territory (being right in the middle of the Encapsulated map) and is now something like 15 hops from my space. Wonderful.
In unscouted territory with a Brutal AI.
EDIT: Scionox is The Hunter here.