Killing someone's mine pyre when it's a flat 7 day burn time is a brutal blow, especially if it's mid burn. Could the time to burn a mine pyre be shortened after X days have passed since world start?
Example: L1 Mine pyre takes 7 days to burn, but after IRL day 10 of the world L1 Mine pyres have their burn speed increased so it only takes 3.5 days instead of 7 (or whatever feels balanced).
Each tier of minehole gets the buff at 3 + 7*Mine level days so that there's an advantage of being the first down by a couple days, but people lagging aren't permanently locked at X days behind because their pyre got put down late or destroyed.
The exact # days between catchup phases and the % speed increase were just spitballing, whatever feels right works for me.