A rogue with ranks in perform or profession: bard would work as an alternative, if you wanted to remove magic (even magical music) altogether.
Another quick-and-dirty idea is to take the bard class and replace the spells and spell progression with rogue talents, which would be gained every other level like a rogue. The exception would be sneak attack related talents, unless the character has Sneak Attack from multiclassing. Advanced Talents can be take after level 10. Actually, I think this might work out well, since the Bard's spells are usually utilitarian.
Not sure about how balanced it is, though.