Yeah.... but the game's practically over by that point.
I did start a new engineer last night since I love the class so much, which I'll dabble with on the side while I primarily work on the vanguard, who's about halfway through ME2 currently. Plan with the engineer is to romance Kaidan in ME1, Thane in ME2, and then hook up with Kaidan again after Thane inevitably dies. Need someone to fill the gap while Kaidan's dickering around on Horizon / laying in the hospital! I'm curious if you still get the Thane romance stuff in the Citadel DLC if you've hooked up with someone else afterwards.