All of the books sound great, but I do have to agree about the Romulan War and Unworthy covers. IMO they're both boring and rather poor quality. Especially The Romulan War, IMO the picture is just weird looking. My only complaint about Unworthy is that it's another shot of Voyager, which we already got for FC. As for the others, I actually don't mind them so much, except I don't care for the way Riker's vest uniform looks with the shirt open like that. I do love the Precipice cover though, it's just as awsome as the other Vanguard ones, and I'm rather indifferent to Sorrows. It's not horrible in anyway, but there's nothing particularly awsome about it.
Now as for the descriptions, those I love. I think this is probably the most excited I've been for an entire group of Trek books in a while.