I could be wrong, but I'm almost certain shifu does not affect the dot.

I don't agree it gets all that complex, even at 70.

The general idea is to use hagakure whenever it's possible (as long as you don't overflow with kenki). Best time to use Meikyo is when you have zero letters (kasha, gekko and yukikaze) but even if you have one using it isn't a bad idea (supposing you have the gekko letter you would do -kasha, yukikaze, kaiten midare, yukikaze).
Yaten + Enpi is your disengagement combo and Gyoten is your gap closer. Meditate during downtimes. Have Giganbana on the target always (unless the boss is about to die or go immune). Use Guren whenever it's up.

Job is very forgiving and very little punishing. Even if you use Midare and forget to use hagakure, don't worry, dps loss will be minimal (and if midare crits, your mistake will result in a dps gain xD), just use hagakure on the next 3 letters.

Sounds complicated but it really isn't.