In issue 58 of my Dungeons & Dragons zine, d12 Monthly, I give a newer version of the magic-user class.
It’s not at all dissimilar to the B/X magic-user you know (although there are some changes), but given there are only four classes in the issue (where all other classes can be based off), I thought it worthwhile explaining a little more about why I created it all this way, and why I kept the term magic-user, while changing the thieve and fighter.