I like your thoughts but you don't avoid the problem of the HIVE crash. If HIVE crashes, HBD's marketcap will go over 10% of HIVE's and then we get into the negative death spiral that brings HIVE lower and lower and lower.
The best way to make a stable coin in my opinion - whether tied to usd or to match inflation - is to do it the way DAI / Maker DAO does it. We could do that here on HIVE but will require some additional smart contracts in the blockchain code, which is not to hard to implement.
However, the current form of HBD is very useful to HIVE users. It takes dumb money from a investors who do not look at what they buy and algorithms that only consider prices. They buy at $5, $10 and $15. Meanwhile content creators here earn tons of money. Also, for the next cycle, this will multiply the Hive DAO payments, increasing the funding for projects that benefit HIVE.
So, I'd say, let the market give us money! Let the idiots help us.