Ember farming was a chore before and even worse with the reduced drop rate. Before, I’d spend dozens (sometimes over a hundred) of embers to build just one item.
Right now, EXP has no value at all after max level. So my suggestion is that every (x) amount of EXP obtained after max level grants a number of embers to the player.
This gives exp a reason to exist past max level and provides a consistent way to farm embers.