Bushido is used for:

Honor - the Virtue, on your paperdoll, dlb click the pentagram above your avatar, then the cup on the gump. Make a macro that "Invokes" this virtue 'cause you should be using it a lot. What it does: Every successful successive hit increases your perfection 1 "step". Each "step" increases damage 10% up to 10 hits or 100% (above the previous 300% cap) if you miss you go back 3 "steps". It ALSO will give you Health/Stamina/Mana back after a kill and more times than not will fill you to 100% (dependant on what your killing and how many "steps" you have in perfection.)

Critical Strikes - When using Lightning Strike, you will have a % chance to land a "criticial strike" which basically is a hit that goes through without being effected by your targets resists. % chance goes up to 20% at Legendary.

You could drop Healing to 90, Chiv to 70, and if your skill cap is 720 that should give you enough to GM. (I like better chances at critical strikes, so I'd also drop Anatomy to 100 and Tactics to 110)