If you are still wondering about splitting path bonuses I have a suggestion. Make a new Rune Slot that is specifically for the path bonus. The default rune could be set to be the primary path's bonus. The second rune option can be a 50/50 split of the path bonuses. The third rune can be a 25/75 split.
Inspiration can have a different bonus to offer. Default is set to the % potion/elixir efficiency. The second rune can be % of missing health restored every 5 sec. Third rune can be % of missing mana restored every 5 sec.
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