A couple of things I notice:
1) As has been said, the tiling factor is too much. [v] was pretty clever with their usage of tiled maps on the Demon. The details on the maps matched or suited the places to which they were applied, even if the actual geometry was lacking. The overall effect is that the textures look much better than they would if they'd just been slapped on as they had on the aeolus, triton or many other FS2 ships.
2) The mapping is not symmetrical. Symmetry is one of those reasons the Demon's somewhat odd textures look like they're meant to be that way.
3) You're being way too conservative of polys to be honest. The whole reason for the rebuilding of the [v] ships is to build the ships as [v] would have if they had a much bigger poly budget than they did. The HTL engine is very powerful. As long as you keep the map count to a bare minimum (1 big UV map would be nice
), the ship may as well be 50 000 polys, since it's not going to greatly dent performance. Remember that the number of copies of these big ships in a mission is also of little concern.
4) Just step back and take a look at the Demon to determine what details should be modeled in, and then model them! The textures and geometry must work well together and complement each other if the ship is to look good overall, and the best way to do that with HTL ships is to get the ideas for the geometric detail from the textures themselves.
You could try something like this:
http://i5.photobucket.com/albums/y184/VA--Twisted_Infinities/Misc/Hecate_Outlines.jpgIt's an old image I used to help Grimloq get ideas for things to do with his hecate. It's basically a combination of highlighting detail-worthy texture features and new geometry ideas. I could do a similar one for the Demon if you like?
