I may be wrong, but I believe this sytem is flawed in the same way Encoin is. It assumes an equation will remain constant over time but it is more likely that it will vary. I'm referring to the assumption that an increase of X in difficulty will equate to an increase of Y dollars in the cost of mining. In the future that equation may change to X*1000 difficulty = $Y in cost, so because difficulty can only adjust linearly then at some point it will start playing catch-up with technological progress and so hyperinflation will ensue because it will always be profitable to mine.
Now if only you understood that an increase in X difficulty is an increase in Y cost is precisely
not how encoin works, maybe you would feel differently. It is based around market factors and incentivizing the creation of coins when it is profitable, and accounting for it when it is not in a way that still keeps the network secure.