I think you have a good grasp of the situation. I would think for the 357, you would full length size every time. When you purchase your dies, get a set that has a carbide sizer. You will not regret getting it. you do not have to lube your cases to re-size when using carbide, you will if you use a regular sizing die. For the 308, it would depend on your gun and how "hot" you load whether to partial size or neck size. Some Handis can get by fine with neck sizing only (if you have light loads) and some need to to be partially re-sized every time. Of course if you fully re-size every time, you will avoid problems altogether. Partially resizing is not difficult, you just have to make adjustments to the die in small increments until you get it just right. Good Luck and Good Shooting