We love to praise linux constantly and tell everyone to change to it (they should) but what are your biggest annoyances ?
Mine would be, installing software (made even more complex by flatpaks being added, among the 5 other ways there already were to install software) and probably wifi power management issues.
Bluetooth support can be a mix bag one point my keyboard constantly disconnects for every few minutes likely due to the hardware aggressively try to save power.
Suspending can be 50/50 especially on old hardware. Either you get it back up and running or you will have to forcibly shut it down since it refuses to accept any commands.