Yeah, I think the big appeal is to essentially double the variety the game already has, and to provide hardcore players with more ways to have Fun. Thing is, that only really is going to appeal to people who play the game a whole lot already... even if they aren't that good (like myself).
As far as priorities to focus on, I think the objectives screen does definitely need an update, but I don't really know what else. The expansion's content has felt really stable to me and it's all worked. It's been great. I'm working towards getting the showdown devices (very slowly) to see if that outright murders me or something.
Edit: Incidentally, I have encountered so many missile guard posts under force fields and that is seriously like the most powerful combo out of those very common things the AI could possibly have as defenses. Bombers can't get the force field else they instantly die to the guard post, and missile frigates and fighters don't really work all that well against the force field. Raid Starships will also die instantly pretty much as soon as they get into range. I've been defaulting to the slow approach, but lord help me if I encounter that combo also covered by a fortress that is in range of the missile guard post.