I was completely disinterested in the Brawler and Martial Flexibility ability until the Familiar Folio came out.
The Eldritch Guardian Fighter gives you a Familiar (that's cute), and at level 2 you can grant it any combat feat you possess, provided it can see and hear you.
Combine that with the new Mauler Familiar archetype, which, at level 3, allows your Familiar to swap between its standard size and Medium size at will, gaining a Strength bonus and any Strength bonus it would have gotten from scaling up in size, and then getting more Strength as it levels up instead of Intelligence. Instant tag-team partner.
Imagine flanking an enemy with your Medium-sized monkey and taking turns dragging or repositioning the poor fool around the room while the other rains down attacks of opportunity with chair legs or stools or doors.
Some day my Osirian wrestler, Sandy Ravage, will rear his ugly head, and Golarion will never be the same.