The level idea was just an example. It could be something different like getting a certain achievement or having a set amount of galleons, but it's never going to work for every possible form of activity. If it did, there's be no point having the system in place.

Realistically though, if you have an account that's level 7 or 8 and you don't log in for over a year, the chances of you logging in again are extremely low. Like, 99% of the time.

It could also be made so that anyone who used to be staff will never have their account deleted, because that might mess up the staffbooks and things.

This seems like a good idea to me. It would help filter out inactive users, but I also agree that it would be upsetting to have your account deleted if you put a lot of work into it.

Perhaps there can be a system in place so that accounts, say, over level 10 won't be automatically deleted? The majority of inactive accounts are level 1 and profileless anyway, and if you hadn't hit level 10 before you went inactive, you could very easily remake them or start over.