The nacelles used here are essentially the Class F's but shortened and fattened a bit and some of the detailing will be similar to get something of a familiar tech look. Same with the TOS era signage.
These designs are meant to fit into a starship's flight deck area for temporary accommodation when needed for specific missions. The scoutship above would be roughly analogous to a DS9 era runabout and thus be faster and have longer range than a standard Class F. The scoutship's main function would be fast transport for starbase personnel to get to other nearby worlds and systems as well as for deep space rendezvous with other starships.
Presently I'm classifying as such:
- general multi-purpose shuttlecraft (TOS)
- fast long-range scoutship ("Slaver Weapon")
- heavy lander ("Mudd's Passion") - For surveying high gravity and extreme environments. Low warp capable.
- aquashuttle ("The Ambergris Element") - For surveying aquatic environments. Non warp capable.