It may take a while for your Focus to smooth out. If you are concerned about the shifting habits of it, you may want to bring it into the dealer to verify it is running correctly. If you feel it is an issue, please PM me with your VIN, contact information, mileage, and servicing dealer information and I will try to help.
Hill Start Assist is a feature of the PowerShift transmission. It automatically operates when a slope of 5 degrees or more is calculated, so you are on a smaller incline it will not activate.