While my alts in STO don't have a ton of ships, my main character has had both the main shipyard and the dry docks filled to capacity, leading to an inability of testing out new ships.  So...I guess it was time for some early-semester cleaning.  I went through and I got rid of ships that were either received by leveling up the character (Tier 1 through 5 ships), and ships that I could reclaim for free either through the event store, or through the C-store.  Any T6 ships I had leveled up already are also gone. I ended up keeping lockbox and lobi ships that I can't reclaim.  Here's what went away (too bad too! I could have promoted all my BOFFs to captains and given them a ship ;-)  ):

1. USS Krioneri NCC-93264  (Breen Plesh Brek Heavy Raider T5-U)
2. USS Athena NCC-93108 (Chimera Heavy Destroyer T5-U)
3. USS Narbonne NCC-93259 (Assault Cruiser, Enterprise E)
4. USS Kriopotamos NCC-93496 (Breen Chel Grett Warship T5-U)
5. USS Freya NCC-91782 (Kobali Samsar Cruiser T6)
6. USS Cassette NCC-92888 (Heavy Escort Refit, Thunderschild class)
7. USS Monte NCC-93016 (Light Science Vessel, Oberth class)
8. USS Nebuchadnezzar NCC-94228 (Dyson Science Destroyer T5-U)
9. USS Guayaquil NCC-93135 (Light escort, NX-01 class)
10. USS Mythos NCC-93744 (Advanced Research Science Vessel, Nebulla class)
11. USS Sphinx NCC-93455 (Tactical Escort Refit, Sao Paolo)

Now I've got more space for my T6 ships that I need to level up and earn those traits!

Thunderchild class