Here's a defensive-minded feat for melee characters who specialize in sword and board. It's modeled to be an alternative to using Acrobatics skill checks to circumvent foes.
GUARDED ADVANCE [COMBAT]
You are skilled at navigating through a dangerous melee behind the protection of your shield.
Prerequisites: Shield Proficiency, base attack bonus +1.
Benefit: When wielding a light, heavy, or tower shield, you may attempt to move through threatened squares without provoking an attack of opportunity from an enemy. When moving this way, you move at half speed. Make a combat maneuver check against a foe who threatens you, adding your shield bonus to AC to the check. If successful, you do not provoke attacks of opportunity from that foe due to movement. You may attempt to use this feat against multiple foes in 1 round, but each additional foe increases the DC by 2.
Special: You can move at full speed by increasing the DC of the check by 10.
If you've got a final version of this, why not post it over at the Pathfinder Database?
Didn't know about that website. I'll take a look.