I have a Warpriest (Sacred Fist) of Sarenrae that has Crusader Flurry so I can flurry of blows with a Scimitar. Warpriests of Sarenrae can also cast Flame Blade which is "wielded like a scimitar" for feats like Weapon Focus, Improved Critical, etc.
Would that allow me to Flurry of blows with a Flame Blade?
Yup. Get your flame on.
you might wish to also look at flame blade dervish feat. espacily if you also have high cha.