Launchable fighters come pre-fab, but you can completely customize a fighter if you're piloting it.
(See P&N - Border Wars)
Note: Piloting a fighter is very handy against ships with heavy missile payloads, since they can't target you
Point defense cannons and lack of space for equipment are the downsides.
You can create new "enemy" designs to your taste and have components reference them as launchable units.
You could even make launchable ships, though you'd want the "Carrier" to be much bigger
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Do be careful not to create a carrier that launches carriers, that launch carriers, that launch....
Things would get out of hand quite quickly
[ December 18, 2003, 02:51: Message edited by: Suicide Junkie ]