How would you enforce those non-free transactions? If the transaction spammer is the miner then he can include any fee whatsoever because he pays himself. The only cost for him is that the coins are frozen for about 100 decaminutes.
You're thinking of the current network. We're talking about a hard fork. A hard fork could require all transactions to have some sort of minimum fee included.
Either we've gone through the looking glass, or else the goal is that Bitcoin should fail and some alt coin take its place?
Why hard fork Bitcoin to enable microtransactions if only to make them too expensive, as well as add risk and cost and also remove functionality in the process?
Gavin's 2nd proposal also seems worse than the first by the arbitrariness factor. x20 size first year, for years two through ten x1.4, then stop.
Is there some debate method outside Lewis Carroll where you get increasingly absurd until folks stop talking with you, and then you declare victory?
Lets stop this painting-the-roses-red stuff and get back to serious discussion if we want to increase the block size limit at all.