An interesting metric for mining incentive stability is the amount of fees available to a block and immediately after a block.
E.g. this old chart: Red is the fees my node's blocktemplate before processing a new block, green is the fees in the template immediately after processing a block.
A chart like this could reasonably have a third line: how many fees were in the block-- which would hopefully be pretty close to the red line, but it would be interesting if it sometimes wasn't (empty blocks being a known example, but are there others?).
One could also imagine additional lines-- how many fees would be available two or three blocks out assuming no further transactions arrived.
fametrano
commented
4 years ago 
An interesting metric for mining incentive stability is the amount of fees available to a block and immediately after a block.
E.g. this old chart: Red is the fees my node's blocktemplate before processing a new block, green is the fees in the template immediately after processing a block.
https://people.xiph.org/~greg/temp/fee_avail3.png
A chart like this could reasonably have a third line: how many fees were in the block-- which would hopefully be pretty close to the red line, but it would be interesting if it sometimes wasn't (empty blocks being a known example, but are there others?).
One could also imagine additional lines-- how many fees would be available two or three blocks out assuming no further transactions arrived.