I'll try to make this as spoiler free, but no guarantees.

Day one: I played about 6 hours solo and was quite disappointed. Chapters 1-9 are 100% story mode. This means you have to repeat it on each toon. It was also very linear. I didn't even so much find a treasure chest or anything worth the time to look around.

Day two: Almost didn't even bother... But I slogged through and got to the point where you build your base. This is where the game opens up. It REALLY REALLY opens up. A few downsides is that again, each base where the story guys are located, are in a story mode area.

Day three and four: There's no end in sight right now so far as to collecting followers, building and leveling them etc...

Spoilers below!



Thoughts:
Very disappointing at first, but once you get past the first nine chapters and get your ship back, it's a lot of fun. I have yet to see any impact of choices that bioware said would be so important. Darth Marr dies no matter what, as does the HK droid. Everyone still joins your cause regardless of answers. All choices good or bad raise your influence with that npc character.

Diplomacy is very over powered tradeskill now. Just shower your companions with gifts and watch them become gods. Hero of the story (me) 62k hp and 2300 damage. Level 7 flunky... 87k hp and 4000 damage and spams 15k hp heals.

There is a triple opt in to start the expansion. All your companions get taken away, but are replaced with dozens more. Downside is that all companions are the same now, just different aesthetics. Even if you go back to fleet or other planets, they are gone. As a Sith Warrior I have only found Lt. Pierce so far in one of the alert quests. I do miss Vette. So if you haven't maxed out your companions affection yet for the +10 presence bonus, you will be unable to do this after you start the expansion.

The companion window is pretty nice. It lets you instantly warp around the game. Figure out where your idle companions like to hang out and you just warp around everywhere now instead of walking. Warp to this guy because he's next to the bank and vendors. Warp to this guy because he hangs out next to the mission terminals. Warp to all the turn in guys. Warp to the planet from the quest window. Quick travel around the planet on 0s cooldown. Warp warp warp.

I hit level 65 very quickly. About three hours into the expansion just doing the linear questline you are on. Level 65 is a joke now that every planet and dungeon has you down level to make it "challenging". Lv65 is more like a simple differential between a sub and a non sub because they were too lazy to find a way to restrict free to play players from equipping expansion equipment. It's quite annoying because MOB's now agro on lower level planets, and they don't die in one hit.

There is a lot of focus on unlocking "legendary" status. What they should have done is combined your alts into the same alliance base. So instead of some random npc running the smuggler and supply lines of your new base, it's your actual smuggler character while you are running your Knight. All of these characters are stuffed into that storymode zone so it shouldn't be hard for them to pull your account or legacy data for this. Because all the classes have the epic story and are the heroes.

All in all. I would give the expansion a 4 out of 10 for the linear chapter storyline. And a 8 out of 10 once you finish chapter 9 and it opens up. As for boxing... I went from 4 for a full group originally. Dropped down to 3 a while back because it was just easier to let the companion do the healing. Now, there is little reason to do more than two box unless you plan to solo operations (raids). Just run 2 dps toons and have one companion set to heal and the other on tank duty. The companions are just insanely powerful at low influence levels, and if you level them to influence 50, they should be getting their own movies from Disney.