You need to divide the 1% inflation between 70-90 BP's getting paid.
The inflation is the sum of all rewards, by definition. I refer to this as "rewards" in the formula. Since accounts are effectively cost-less, it the count is irrelevant as a single entity could have many.
I would say dpos inflation is more similar to PoW than you are describing
Its really, really, REALLY not.
In POW, consensus is NOT closed-body. Even if no tokens are exchanged in a POW chain, the ownership of consensus can change drastically.
One important phrase is "award those responsible for consensus with rewards that give more influence over consensus". This is really key to understanding the difference.
This makes EOS not really a closed system
EOS is not an isolated system. I suggest reading the updated section to understand the difference.
BP's can sell their tokens for whichever currency they use to pay their expenses
This is in the formula, as ep. It just delays the effect, as mentioned.
RE: Inflation, Centralization, and DPoS