Bostineaux is very good in the 60s, but wherever you go be aware that after 50 it's really important to sub a job that has access to sneak/invis if you play solo. Bostineaux is amazing but it gets really awkward if you don't have a form of Sneak to get around.

Dancer is a wonderful solo sub for melee in general and Samurai in particular; getting it leveled should be an immediate priority for anyone trying to get a melee to 75 in this day and age.