I give it a "B". I love the space combat, but the ground game is, to use Ward's word, atrocious. I don't know who designed that part of the game, but they need to understand what "point of view" means, and how it relates to your character constantly changing enemies in different directions while you're under heavy fire and unable to focus back in the direction of the biggest enemy fire because your character is too busy focusing on the one little guy with the peashooter instead of the damned powerful Romulan with the plasma grenades!
There's a setting in options that will auto-prioritize based on threat.
The game gets a lot more interesting once you get passed the Lt grades, which serve only as an extended intro to game mechanics. There's several memorable LtC through captain missions. They aren't hard if you solo them, but bring a challenge if you have 3 or more people with you as the difficulty scales. Some of the Admiral stuff is damn tough no matter how many people you have with you.
So, it needs some polish, yes. It should be much more rounded out in a couple months, especially with all the klingon additions they're making. I've set up to buy 3 more months when my trial expires in 2 weeks, I figure that's enough to see whether the dev's are committed to making this shine or not. If they are, I have no problem dropping the money for a lifetime sub. If not, well, I don't renew in June.