It's all good road and no problems until you get to Helper, then it's twisty and steep but not really too bad. Google Earth it and go to street view for pictures.
I have only driven the very Southern portion of UT-72 to get to Fish Lake. I recall it being a decent road with no really steep sections. I have also driven US-191 from Helper to Duchesne a number of times mostly going South. Going North, there will be a steep climb out of Helper with twists and turns and narrow shoulders. I believe some of the grades are 8%. The summit is about 9,100' in elevation and then you decend to Duchesne and Vernal.
