I remember some time ago that nep(or someone else idunno) buffed leverage for high str. How reliant are other staff/spear spec skills on str if at all? For example would I see misdirect being a big dam option? Or longer lag? Does spin fore of skill percent or something different?

Leverage last changed in 2012, but it wasn't related to strength.

The user's strength increases the damage and the defender's strength counters that increase. Ideally, you want to be a big/strong warrior fighting a small/weak opponent.

Misdirect is purely skill based. It's strength is that while there are a couple of less common of affects that make it less effective, it's impossible to completely prevent.