Welcome! No other forum I'm aware of. As far as activity, this is pretty much it for Hawaii. Not a lot going on there, it's as laid back as the Islands are themselves.
A lot is due to the fact you cannot listen to the Police, Fire or EMS on Oahu because they use Digital Provoice. I live part time on the Big Island so never get the opportunity to be on Oahu with my scanner to truly tell you what else is worth listening to.
You also cannot properly monitor Maui due to their current LTR Multinet TRS, although I have had success listening to the individual channels in conventional mode. Maui is due to switch to a P25 TRS "soon". By soon I mean Hawaiian time, the TRS is up and "running" but not much heard on it yet and no word on when the switchover will be.
Kauai has a Motorola TRS but it's very quiet. And the Big Island is mostly VHF Conventional. See the Thread recently that covers that in some detail. The Big Island is also supposed to be standing up their own P25 TRS sometime in the near future.
There's also PACMERS and some other Military/Federal TRS' as well as the Statewide TRS (I've never heard a peep on it).
Basically there are things to listen to just not a lot of discussion about it here. You can go months without seeing a new thread.