There are no reserved arcana, however I would only allow PCs to pick from the first nineteen of the Major Arcana, so exclude Judgement and World. Also there would be a limit of no more then two of the same Arcana for PCs. 

There will be Social Links, in a manner of speaking. You will obviously interact with each other and various NPCs throughout the RP. My plan was that as you interact with one another and with these NPCs, you will learn more about each other, grow closer, and become friends. The further along this path you tread, the more benefits will be conferred. These benefits ranging from new abilities for your Persona, maybe stronger elemental resistances, or if the growth is between two PCs, something more. These Social Links are each individual and are only limited by the amount of PCs and NPCs, meaning you can form these bonds with anyone that it makes sense to.