Our site is 10+ years old and recently imported to Discourse. There are a lot of inactive account and many people who exclusively lurk which is why TL1 is so high
Non-default settings:
(Default 10)
(Default 12)
Maybe the extra duration is helpful. Personally I think if you’ve been active enough to reach TL3 you deserve to be there for a while
I’ve actually found TL4 to be useless in my case. Currently its just redundant with the moderators