Agree with most everything you said, but I still believe curation rewards should be 50%. Even if that only makes the difference between $10 for the year or $20, that difference still matters.

It also does make an important difference to the value of STEEM because it determines the rate of dilution. Content rewards go to authors (successful bloggers for the most part) and dilute SP holders as a class. Curation rewards come back to SP holders as a class. The change that cut curation rewards in half (actually more) had a significant impact on the value of STEEM, even if not specifically cutting the value in half (because of the remaining value from influence; also long term potentially network access)