I meant to ask: If there's only a value cap, that'd mean a miner could trivially blow up the blockchain in size by adding a bunch of near-zero transactions and everyone would accept it as valid.  

I'm sure it can be worked around, but would involve some sort of upper-bound cap.
 
As far as rolling out the ideas, it's hard. Something like Litecoin is perfect because it has actual value, which is the only real test of the hybrid systems, to be honest.