Yeah, there are issues with cash, although that seems to be the only way out. Storing cash is problematic but may be if one is investing small amounts, it is ok. Also, by p2p i thought you meant, people are able to get cash online after selling bitcoin. which is why i thought one leg has to be cash. The source of cash can also lead to problems. Given that this is a new tax source for the govt., i am sure agencies are tracking developments in this space very heavily.

regarding premiums, there isn't much one can do. There is just a very strong case for more exchanges to pop-up or p2p portals that can allow fair trading of bitcoin - the potential for user acquisition is immense.