Added a sub-section on Weapon usage priority to the How to get strong quickly section of the Leveling Guide.

Weapon usage priority
(LB# = # of limit breaks; SLVL = weapon skill level)
SSR dual-skill > SSR Assault > SSR Pride > SSR Defender > SR Assault > SSR (off-element)
LB3 SSR > LB1 SSR Assault = LB3 SR Assault
SR Assault SLVL10 > SSR (off-element)