Some critique:
Can you read my kråkfötter?
I think the model has been dirtied up too much. Looking at the wing it looks more like rock than metal. I would suggest that you go back into creating a "metalbase" which looks really nice and then start adding dirt to selected places where you would be likely find it. A tutorial I watched said that your modelpiece should by itself "tell a story". You probably already know this, but reminding won't hurt ^^
For example in the image I put a suggestion that you'd sample some of that "oil dirt" and put it on the engine as if it was leaking - it being warm and all might melt things. I like parts of the engine which I haven't marked (the cracked one) - the edges looks worn as if damaged by heat. That engine is also the part of the ship which looks the most like metal. You could also add streaks of black burns behind the engines on the sides - as if extreme speeds produce heat which burns the ship itself.
The "organic"/curved lines marking isn't something which would be produced at a manufacturing station. It's not the curvyness per se (my english fails me), but moreso that they are wiggly. Something "manufactured" by man would have perfectly "straight" curved lines if you get what I'm getting at
The bottom was too dark for me to say anything about.
As for why it is low res.. Is it mip-mapping? Does it look like this in UDK? Are you perhaps trying to cover too much UV-space with your 2048 (More effective UVs?)?
I'd also want to see it in UDK once you've gone at it again
Merry christmas everyone!