I built the Excalibur in 1980-1981. Since then more material has become available detailing the interiors of warp engines, other aspects of the Constitution class starship, and the effects of phaser damage. So, if I had this to do over...
I might have corrected more of the shortcomings of the ERTL/AMT Enterprise kit itself, most notably the shape of the superstructure atop the saucer.
I exhibited the model at a Sci-fi / Gaming convention near Detroit in 198.. 2? 3?. Someone asked why I didn't coat the corridors with frosted atmosphere and crew smears. Well, I might consider using a pearlescent paint to simulate the frozen atmosphere - assuming it had time to freeze to surfaces before escaping into space. As to the crew smears... eeewwww!
We saw the effects of phasers on unshielded, or minimally shielded, ships in Star Trek II: The Wrath of Khan. So, phasers alone probably wouldn't have caused the big, gaping holes and gashes that I put on the model. I suspect the majority of crew deaths are not due directly to blast effects and asphyxiation, but due to radiation from the blasted warp engine and other collateral damage effects.
The insides of the model's warp engines don't look very much, if anything, like the semi-official blueprints and cutaway posters that have come out in recent years. C'est la vie - ou la guerre!
Given that the 12 starships each have a unique uniform chest insignia, I might have made unique pennant decals for the secondary hull and warp engines - maybe something on a sword motif.