The test rules are made so the testers can more accurately gauge your skills. It doesn't take much to drop a laggia/dolkka/ophion so running a dino/evilswarm rabbit deck won't show much. In war matches, the basic idea is just winning, not necessarily which is the more skilled player. There are no points for originality in wars - just straight win/loss - so there isn't an added banlist in them. As far as adding an option for an additional banlist in wars, I'll have to consult with Nichigo. He does most of the rules - I mostly deal with the numbers. Don't be surprised if he says no - introducing new rules that increases limitations usually hurts activity than helps it.
BTW - crossfire and double/no elimination are just rules in determining how/if you can knock out an opposing player. They have no bearing on banlists. So hypothetically, if special banlists are allowed, you can have the banlist in a crossfire or double elimination war, etc.