#2 is easiest with larger size ships. Continuity is difficult and I find I use interior construction kits by vendors here and there.

Example: 3-D-C (renderosity), Coflek-Gnorg (renderosity), Stonemason (Daz), AntFarm (Daz) has some good spaceship interiors as well.

Also, Coflek-Gnorg set has some expansions at content paradise made by another vendor with Coflek's permission that extends their use even more.

 

EDIT to add> The expansions for Coflek-Gnorg's sets were created by Meshworks.