firstly, golden (rare) crates have NEVER given diamonds, so that shows how much attention you have been paying. There is 49 blue (uncommon) crates in the 150 crate order. This means just under 300 diamonds in the whole cycle. So yea, it's hard for free to play to get diamonds. I'm not arguing that. But this HAS NOT CHANGED from the way it was before! The only thing that HAS changed is the amount of epic cards has gone slightly up, and the credits have gone slightly down.
Not a big fan of the diamond re-entry to blitz, but that wasn't changed in this change. So why are we discussing it now? And what does balance have anything to do with the vault? Your argument is a buggy mess in and of itself.