Not sure why vehicles.txt would have to be edited. If you mean removing ship classes, I think honor could take care of that. Otherwise, perhaps I missed a suggested change or two somewhere...
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I once played a game with Lord Chane where we did something a LITTLE bit different. We limited fleet sizes to 10 ships. Gentleman's agreement. So, even with ships of any size, it was hard to take large and huge breathables. I guess because people knew there could only be 10 ships in a fleet, so it became more worthwhile to build WPs as it became more possible to defend planets. So, in a way, "ankle-biting" will be a bit similar, I think. Of course, with 10 ships to a fleet, there was a finite limit of total tons one could throw against a planet. It wouldn't be the same with 100 frigates...
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