I can see that replay speed, as important as it may be now, is going to be even more so as we get into 100 million blocks, not to mention 1 billion, etc. I know it's a ways off at our current rate (I guess things would change if we had a significant increase in user activity), but is that something these current modifications are going to help with, especially when our rate of block creation is running at twice or thrice the speed it is now? So, basically, we'll have storage issues unless we can continue to compact things, and/or speed replay issues, right?

Also, I'm wondering, if I'm reading this correctly—in v. 0.20.9, there appears to be a difference of 157 minutes between replaying 20 million blocks and 25 million blocks, but it's up to 186 minutes between 25 to 30 million blocks. Did the blocks get heavier with more transactions between 25 and 30, or is there something else at play?