I was looking for a way to add stealth as a class skill to this build, and came across Divine Tracker archetype for Ranger. This lets you get improved unarmed strike for free if you take Irori as your deity as well as favored enemy/track and some additional class skills.
You lose 1 CMD from the second rank of Weapon Guard, but the bonus feat is made up for with the Divine Tracker bit.
I think you also end up with higher saves, but to be honest I am not sure how that is calculated.
Working on the Kirom Lancaster (Duelist) build, I am going for nearly this setup except that I am hoping to be the party scout as well.
I was looking at going first lvl ranger instead in order to get stealth as a class skill + favored enemy can't hurt. One cool thing I noticed was that the Divine Tracker archtype replaces wild empathy(useless to me) for a free improved unarmed strike feat so long as unarmed strike is my deitys favored weapon! Beyond this I figure take the remaining 5 levels in fighter(weapon master archtype) still gets me all the important bits.
I am still a relatively new player to all this so if someone could please double check this for me it would be greatly appreciated!