Some overall feedback now that's I've played through more of the content:
I haven't added any of their ships to my fleet, but from fighting them they seem fairly well balanced with the base game. Maybe a bit difficult early due to their good shields (and phase ships are annoying just by default), but once you have the firepower to get their shields down their armor is paper thin and the hull may as well be made of plywood. The designs are mostly fine - they're visually distinct without looking overly bizarre - though the recolors (ie: the blue onslaught) could do with some structural changes to differentiate them more.
The unique quest ships and weapons I've avoided using though simply for being overpowered. Personally I really dislike it when I'm essentially forced to use a mod's content simply because power scaling makes anything else effectively irrelevant, but fortunately that wasn't the case here - so far I'm at the point after defeating the theater organ without needing to use anything that's wildly outside of what's available to more or less vanilla content (meaning: my fleet anchor capital ship is a Paragon with 5 S-mods from Progressive S-Mods, Legendary modifier from Starship Legends, and upgrades from Exotica Technologies, but it still only uses vanilla hull mods and weapons; non-player ships also get modifiers from Starship Legends and upgrades from Exotica Technologies so those aren't player-only power scaling effects). I assume there's still more content - I haven't done anything with the damaged hypershunt in the Helheim system or the Voidbreak black hole that's outside the map - but I like that there so far hasn't been anything that's been power scaled to the point that it can only be defeated with ever more powerful content from the mod itself.
The quest content so far has been interesting, though the fight against the three tesseracts was pretty underwhelming (the rest of the Phase Lab fleet got wiped quickly, but the ship with the songs of light was more or less able to hold its own even without much help from me) and the battle to save Chicomoztoc was extremely underwhelming (the theater organ fleet was so slow that it got separated from the other fleets accompanying it, the accompanying fleets got wiped out so badly fighting my Paragon plus the assembled allied fleets that the greatest risk to my ship was running out of combat readiness before the battle ended, and then my fleet defeated the theater organ by itself). I'm also not sure why the Phase Lab is portrayed as being such an overwhelming military power that it cowed the Persean League into negotiations after a single battle while also easily fighting off Tri-Tachyon - it mostly seems like it's just flexing on those vanilla factions for some reason.
The colony crisis was a mixed bag. On one hand I did like seeing ships with 3 S-mods since I think vanilla generally doesn't give non-player ships S-mods often enough. On the other hand, resolving the crisis was rather underwhelming - you talk to someone, they agree it's unacceptable, and then it's over.
I think that easily the roughest part of the mod is the writing. There are bugs (ie: several places so far where variables are not evaluated), descriptions for weapons that are so long that the popup extends outside my monitor (ie: Song of Light and Song of Dimension), and some misspellings/missing spaces between words/the word "the" missing before some proper nouns/some just odd grammar and wording. Some of the dialog options between the player and Eliza (who I've mainly been talking to so far) also seem to become overly familiar pretty quickly given she's a faction leader and you're essentially a space mercenary doing jobs for her.
Edit:
I got to Voidbreak, fought the eternal guard ship, and... I don't think I'm going any further in the mod. I'm sure it's not unbeatable, but fighting a ship that can unphase for like half a second and each time essentially 1-shot or 2-shot every ship in my fleet isn't something I particularly want to try to puzzle out.
