Honestly feel like magic users are far too common and over used, which then leads to magic users becoming dull and mediorce, due the price of runes i imagine only high earning people or nobles would have acess to them in the first place aside from a few exceptions such as the wizards from the wizard tower and so on.
But a commoner with a low income would likely be unable to use magic due to not having the funds and probaly not having the acess to the knowledge of how to cast magic.