[Mauzen]

Filterscripts should always be gamemode independent, if you want them to be used. Add a specific feature without destroying the gamemode balance (e.g. by shops with their unbalanced prices), as some kind of optional addon. Scripts that should harmonize and cooperate with the gamemode should always be in form of includes, with easy modifyable constants for balancing.

I got no specific suggestion, but I hope this helps you a bit with your decision.