If you are interested in the mempool, this link of Jochen is one I like:
https://test.jochen-hoenicke.de/queue/#BTC%20(default),1w,count
For what fees are needed I use:
But Jochems site can give one some more info on the state and history of the mempool and fees used.
If something would break, I think the mempool will be one of the first things that will show it (increae in transaction requests so mempool exploding).
#Bitcoin