Garthanos
Arcadian Knight
I had considered allowing something like this which conceives martial levels to allow unifying maneuvers.
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But instead of for merging access to maneuvers rather to make multi-classing better for Extra Attack acquisition.
For instance something story appropriate like your character is a Fighter who becomes Paladin before hitting level 5 the multiclassing seems designed to punish rather heavily but by tracking EA levels they merge more seemlessly.
What kinds of issues might there be?

Martial Superiority - Making Combat Superiority a standard martial class feature by
Martial Superiority - Making Combat Superiority a standard martial class feature by - Created with GM Binder.

But instead of for merging access to maneuvers rather to make multi-classing better for Extra Attack acquisition.
For instance something story appropriate like your character is a Fighter who becomes Paladin before hitting level 5 the multiclassing seems designed to punish rather heavily but by tracking EA levels they merge more seemlessly.
What kinds of issues might there be?