The idea itself is quite interesting. I'm not sure about some of the bonuses (havent do the math ;)), but I think I would consider adding second perk from higher level. Level 50 is too easy to achieve via Haedrig's Gift. I think maybe 75 would be more appropriate, because its not that easy (I'm a noob I know) and it takes some time to achieve. And some lazy people (like me) ends the season when completing the season journey (GR70 usually) and 2nd bonus from level 75 could make me try a bit harder
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