You can do your best to customize the ship you spawn with the resources at your disposal.
If you can turn a dessie into gunboat prior to the event, more power to you.
If you need "your" gun loadout, knock yourself out.
But no bombers!
Problem with custom things for the GRN will be that they cant dock at Reunion. And after they changed something in their loadout they will loose a few bots and bat on the way back to Orkney, while still being unable to dock there. So a slight rephack would be a very good thing...