Ignatius Mortimer Meen is far too fun a character to be left to languish in a substandard game, especially when he would gel with the mlp world so nicely. His use of cursed books and hatred of academics makes him a perfect antagonist to Twilight, his crusade creates an interesting mirror for Starlight and his style of magic as well as persona is a great way to include Discord.
This is my take on it but I think he'd be a great character to cross over.