So basicly your saying that you can upgrade your proficiency so that your all items using that proficiency become stronger? Definately no. That would mean that I would have to create another item for every item. Every item currently uses 2 items. An unproficienct one and a proficient one. Altogether theres somewhere around 120 new items (i think) which equals to 240 real items. If i would implement your "system", i would have to include another level for every item. That would mean i would have to make another 120 items.
Oh i was only talking about one level. If you think that you wanted to upgrade it multiple levels, for example wanting to upgrade ur proficiency to lvl 2 or what not, that would mean another 120 items, becoming 480 items total.
This idea is just outrageous. Those 240 items took me a ton of time.