It depends a bit on whether non-sidhe old forest can go to 9 - most appear capped at 7 although that could be due to youth / coppicing or other working by humans.
I wondered sometimes about going over 9 in sidhe and possible karamhul realms to reflect faerie ties to the spirit world, etc - 8 or 9 as a "ancient forest" sort of thing with +1 or +2 in special forests to reflect something truly awesome, though likely with some issue associated with it like self-aware spirits and the like who occasionally cause trouble.