As far as smaller ships like Carrack Cruisers and Blockade Runners, it might be very possible to have them flying around the map. I believe the BF2 engine problem does not stem from large PCO objects moving around, but rather having poeple walking around inside them.
I could see people spawning inside a Corvette's bridge at various gunner stations and a pilot seat, and the cockpit would be that bridge. You just couldn't exit the Corvette PCO and walk around inside it like in the BF1942 SW mod.
Spawning players directly into a smaller capital ship that could fly around shouldn't be a huge problem, though.
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