Since nobody else raised their voice in quite a while, I wanted to use the opportunity to comment on some things I've read.
I think the forest should be kept as simple as possible.. I dont like the idea of anyone having property out there or any sign of formal civilisation.
I agree with Xela that the forest should initially not be urbanized. It could happen that someone builds a structure or sets up a garden or orchard or whatever down there at some point by working to that goal by IC roleplay as long as this change would get the okay from the GM staff. But initially there should be no active signs of civilization. Ruins of some forgotten structures, mostly reclaimed by the forest, would be okay in my book, though.
I do not agree as much with the sentiment of keeping things simple. Apart from very few scenes (that usually could use a small part of the forest as a backdrop) you usually are not looking for a generic forest, but for points of interest within a forest environment to make those the scenery of your roleplay. Scenic sights like that big clearing with wildflowers, that crystal clear lake or special trees (either due to their size, their breed or other factors). Apologies if 'simple' was meant in a different context.
Maybe a little treehouse area? suitable for one or two people.
For buildings like that, I would make sure to have them work for at least two people (because we usually roleplay in pairs at the very least).
The temple can really handle druidic rites already (...)
While the temple sure can handle druidic rites, not every druid (and similar character) would feel at ease practicing there unless he or she shares in the local faith. For my druid it would not feel right, so he would go out in the woods and seek for a place that isn't already attuned to a specific pantheon. Again this would not need to be anything more than a little prop - a couple of strange looking stone monoliths, a rather unique tree or just an unusual carving within a rock. As a bonus a spot like that could also be sometimes used for the more grey (or even dark) rituals, that are impossible to pull off at the temple in the first place.
(...) as the forest will largely end up being watched over by the temple's scouts (...)
I am not sure if it is that good an idea to claim that all areas are watched by scouts/guards/knights of the different factions at all times. The immediate area of any faction, sure, but another floating island? Wouldn't it be best to not establish an NPC guard presence in the forest and rather leave that to the active individual roleplay? Again, this could change later on, if, for example, a faction successfully claims the new island and establishes a guardpost out there or something.