It can be worth adding around ¾ of the pomegranate molasses and mixing before adding the rest. It should go a fairly deep brown color and you should have a good sweet-tart flavor. Add the rest/more to taste. If it is very tart, you can add a little sugar to balance it out but it shouldn't be needed.
You can make the dish ahead and reheat. You can either make it up to just before you add the pomegranate molasses, or make it completely. If the latter, just take care re-heating as the pomegranate molasses can burn if they get too hot.
I initially made this with ¾ cup of stock rather than ½ cup. This ensures the chicken is better submerged as it simmers, but I think gives a little too much sauce in the end so needs a bit of time uncovered to allow it to reduce, before adding the pomegranate molasses. Choose whichever way you prefer.
You can use boneless chicken thighs, if you prefer, but the meat on the bone adds to the flavor.