I just made commander, and my character is a science officer. I decided to go with a science vessel this time instead of a cruiser or escort. If you've seen any of the tier 3 science vessels, you'll understand why I named this one 'FlyinMicrophone'. 'Flying Microphone' was 2 characters too long.
Oh, Astro--if you go to the shipyards, there's a guy there who will let you customize your ship. You can do that 1 time without paying each time you get a new rank (and I think if you buy other ships, too). If you choose the advanced option, you can mix and match different things, change colors of the detailing, choose detailing patterns, and so forth. I'll be on later today after I get back from the dentist (have to have a root canal >.< ).
@JediAthos and SWPhreak--if you guys want any tribbles, let me know. I breed a crap-ton of Mattson tribbles to sell on the Exchange, but I'll be happy to send just about any type you'd like. I can make some of the highest tier ones, but the food costs to make those are so sky high I don't have enough money to do those for free. Astro, I'd offer to send you some tribbles, too, but I can't trade you or send you anything while you're on a trial account--the game doesn't allow it. If you get a subscription, let me know and I'll send you some goodies.