Basically, this is my vision for this tournament:
Stage 1: Round-robin – each good faction plays against each evil faction. Choose from the full list, but no more than 2 repeats. (with 8 games, 2 games for each faction + also, if there are no more elves left, for example, then you will have to exclude them).

Playoffs – it's clear. The top places among the evil factions face the last ones from the good factions, and vice versa. Factions are chosen from the full list – if you advance, you can no longer play with that faction.
Semi-final/final – it doesn't matter anymore. :)

Templates are always chosen from the full list.
Plus, there is no need to wait for the next draw; you play when you have the opportunity. This does not violate the idea of the tournament: good versus evil.