OK, honest critique here:
Phaser mounts and windows:
I know that these are minor details and are to be put in last, but they would be something that you can't be without. The clean-looking hull is awesome (I never liked the TOS stuff that had the heavily defined 'gridsquares' all over the hull, but it could use some visable phaser mounts on the hull and a few more windows. Also, in the vein of the phaser mount, do the photon tubes on the forward part of the bridge structure.
The textures are great... and that Welsh Dragon ROCKS, I can't wait to see it with all the details put in.