Wizardry is ‘easier’ than Animagic, but needs time.
So he will learn it after the books 😀
Conjuring and Necromancy are a subspecies of Wizardry (and maybe Animagic).
So depending if its doable with Animagic it might happen in the books-timeframe.
Necromancy would be interesting for him, because he [i]may[/i] get around the Demon Wards if an body is enough to shield him from them (demonic lich!). And it would allow him to get more powerfull, if he could bring himself to consume Animus from people.
Druidic is an good idea, he allready did something more difficult by stealing God power. Getting nature power should be more easier.