[Xrati]

A) Scout x3 Frigate x3 Destroyer x3 Cruiser x3 Battleship x1
BB's don't need expanded versions

(Carriers) Escort Carrier x5 Fleet Carrier x 5
Escort Carriers x3, Carriers x3, Assult Carriers x1(maybe 2)

(Bases) Space Station x5 Starbase x5
Could be expanded through the use of module attachments.

(Transports) Courier x5 Transport x4 Freighter x3
OK, but larger versions will always be the default build.

I like A
B) Explorer, Frigate, First Destroyer, Heavy Destroyer, First Cruiser, Heavy Cruiser,
Battlecruiser, Battleship, Heavy Battleship, Juggernaut.
(Carriers) Escort Carrier, Light Carrier, Carrier
(Bases) Defense Base, Base, Starbase
(Transports) Small Transport, Transport, Heavy Transport
Rescue/Tow ship