Honestly, I think it's fantastic. It gives the game the makeover that we'd all hoped for from Shattered Space and didn't get. This is going to be a bit of an unstructured brain dump, so my apologies if anyone's looking for an overall theme. Anyway!
Cruise Mode is the big thing, it turns your ship from a teleporting mobile home (with fighter pilot minigame) into an actual starship. You can explore space! Find stuff! Get a sense of traveling! If this had been in from the start, I don't think the game would have had half so rocky a reception as it did.
The new PoIs, space and otherwise, are kind of fun. They may wear out their welcome after we've seen them enough times, but I'm nowhere near that yet.
X-Tech is cool. Expensive as hell, but I guess that's the point, And at least you can take your kit with you, so it's at least an investment.
The Database is something else that I've felt was missing from day one. There's just too much world to keep track of, and I'd prefer something that tracks what I've discovered to looking up the answers on Inara which has them all from the word go.
Pets I could care less about. No objection, I'm just not part of the target audience for this feature.
Ranking up powers with QE is nice too. I don't need to grind temples every universe, or sweat it too much if I miss one (or ten) along the way. It does make getting to Phased Time X a little too easy, perhaps. Then again, that's a balance issue and there are ways to address that.
Anchorpoint is fun. I don't know if anyone's noticed, but the hectoring, objectionable NPCs who seem to infest the base gameare almost completely missing in Anchorpoint. I quite happily put off starting the Freestar quest because I don't want to put up with Emma Wilcox sneering at me (or the shitty writing that only gives me stupid things to do so she can sound clever with her replies). Happily this syndrome seems to be absent from the update and DLC. Talking to shopkeepers is fun again. (And I've also noticed that rescued hostages seem to have stopped using the line about needing a shower, which always made it sound as if they felt irevocably soiled by having to deal with the player. Perhaps Beth have been listening - it'd be nice to think so )
The Anchorpoint side quests are excellent, at least those I've engaged with so far.
Terran Armada. Again, I like it. Delta is fun. They seem to have put all the snootiness that would have gone into the Anchorpoint NPCs and concentrated it in Delta. And oddly enough, I love it. He thinks he's the player and I'm the NPC. Yeah, right! Keep thinking that, buddy
The main questline is a bit short, granted, and the incursions get a bit samey, but they didn't outstay their welcome for me. I also like that you can keep the incursions going after finishing the quest. For those who really wanted a Colony War game, that's your war in space, right there.
And the best thing is that I haven't done half of it yet! There's a ton of side quests, PoIs, post main quest missions that I've yet to touch. All in all, I feel my outlay for the Premium edition was worth the expenditure after all.