@ericmacknight I don't think there's a lot of limitations to the kind of plant fibres that can be used for paper. Some are easier to process than others, but I've even heard of waste like fruit peels or the leftovers from winemaking being used to make paper. Heck, you could probably use grass clippings somehow. And there's rag paper as well (usually made from cotton fabric).
If it wasn't for some pens not working particularly nicely with it, I'd point to stone paper as well - but it doesn't work very well with some inks, and I'm not sure what the binding resin is made from so it might not be much better for the environment. I have a notebook from Karst that was an impulse buy many years ago, but every time I start trying to write in it with a rollerball pen I realise why I don't use it much. (The 'stone' is sourced from building rubble.)