There are many other ways to grow the ecosystem without depending on SBD. When steem is big enough, it can support a higher debt and the peg will be more stable.
Arbitrary printing of new money without an option to reduce supply would make this worse than central banks.

Maybe changing the rate from 50/50 to more SBD would be a step to take without adding inflation, although the reward pool is just a drop into a big lake at current market volumes.