


It is not necessary to have an opening for the elbows but the opening does make changing straps much easier.
Personally, I prefer straps without the opening. I just like knowing the spring bar is fully covered. It does require care when changing straps and takes quite a bit more time than the presto strap but if you find yourself wanting to change straps frequently, then the presto strap would be the choice.
The thickness and shape of the padding is strictly personal but the beefier watches would certainly look better with heavier shaped padding (slight to high dome or rectangular) and hand stitching.
A lot of options for you to consider.