Polarized filter reduces dynamic range (NOT ALL THE TIME!). It doesn't matter portrait or something else - if you need dynamic range wider then sensor capability, you will have wether dark face and nice sky or normal face and completely white sky.
NEX has the mode 10 times better then polarized filter - it is HDR. Polarized filter can help you to reduce water reflection (if you want to see fish).
Don't listen to me or somebody else - try! Make several pics with different DR and see that you prefer, it will take just minutes.
But be aware - displays are not capable to reproduce HDR, make pics and then look at final image. And don't forget to make -0.7 EV the same time (maybe even -1EV).
If you send samples, maybe I can help you to improve pics in Post Processing, but be aware - if you have NT monitor, it is very difficult to make a real edit. For editing you need ISP monitor.