I'd personally like to see a cylindrical drydock, like this one from Star Trek:
Renaissance Star Trek: Renassiance Homepage (This model was made BEFORE "Dead Stop" aired, so methinks that maybe some ENT writers are REN fans aswell
)
Anyway, with some TMP light fixtures and some "retro" detailing, this could look really nice.
Another source of TOS drydock ideas can be found in "The Art Of Star Trek", where they show several concepts of the drydock, Spacedock, Orbital Office, etc.
And for those of you who'd like to make some TOS Workbee's, there's a perfect model for ya.
TOS Maintainance Craft