being able to carry a spawnpoint and buy ships aboard ships over a certain size/mass would be helpful
an example, you have a big carrier with dozens of fighters, but only 5 freinds to fly them (this is aside from your drone fighters)
a friend gets shot down, but simply spawns in the carrier and hops in a new fighter
the ship purchase ablitity (with a spawn time greater the more the ship costs) would have keep a fleet supplied in a sustained faction battle (maybe capping the mass/ship cost allowed to be purchased)
An even better method for the mobile ship catalog, make it require blocks in storage on its carrier ship to actually build the catalog ships with, now you must keep supplied, risk lots more resources on that big ship, and a fleet battle doesnt come down to who has more money, but who has bothered to stock more into their carrier, builds more effecient ships, has more skilled fighter (dont blow themselves up)
This resource system can also be used to \"repair\" a purchased ship, it removes all blocks, then rebuilds according to the saved schematic using inventory/storage blocks for a fee of course (this would also work to simply dismantle a mothballed ship)
Additionally this setup would Tie in well with Xyrafyrs idea on Munnitions blocks that take damage as you fire as a way of tracking/removing ammo. Repairing would remove the proper ammo type from storage, and place it in the schematic defined spot in you ship without you having to get out and reload each block by hand