A little dullcoat to get that gloss off the white will do wonders for scale, also.
I've got one of the 1/72 stacks (in sections) in the garage- I think I may go Moonraker on it, also. Maybe take it a step further and make the shuttle look like it'd been through a long service life like what's left of the real fleet. Of course that would mean that Bond had failed in his mission
You're right... the fit of those big tank halves sucked. Actually, the kit had a lot of superdetail potential, but the fit of the big pieces was a pain in the rear. On the external tank, it was so bad that made a mold of part of the tank insulation and then I smeared the tank over with filler along the bad seams (a lot of that) then pressed the mold onto the stll soft filler. Worked pretty good at blending it together.