I'll never understand the argument "People can just faucet 0.0001 TBTC because that is all that is needed for testing!" but then "We need people to be able to mine a 50 TBTC block with a Windows 98!!!!"
True. After 20 minutes, CPU miners should also get a smaller block reward than usual. If the difficulty drops from 1,000,000 into 1, then the total block reward (with fees) should also drop for example from 50,0100,0000 satoshis into just 5,001 satoshis. And the rest of the block reward can be timelocked into some future block number (so that ASIC miners will get it), or simply burned (which is easier to implement).