Rather than have the bridge officers read every dialogue box in the game, I'm suggesting simply that a few one-liners be recorded for important in-game situations, ie. your ship taking fire, raising shields, incoming transmission, 'energizing' the transporter beam when going on an away mission or when hailing your ship while away from the ship, etc. Maybe executing a few of the emergency powers could trigger a voice-over as well.
For customizing the voices, I figure that a pitch, speed and tone slider could be added, to modify the standard male/female voices, which would save having to record a more than the two voices.
As far as monetization, I'd buy a voice-over pack from the C-Store in a heart-beat.
You could even go all the distance and take snippets from the TV shows and movies and merge them "smoothly" together.
The other option might be to register Cryptic as a non-American company. Would that protect them from the Hollywood union? All this licensing and union stuff is just a vile dictatorship!