This looks good to me! One thing you could consider is dividing Necromancy into two styles: Undead Rapport and maybe Life Magic or something like that. Undead Rapport might be commanding/taking control of existing undead (note: if you have your own version of the spell written up as a feature, no need to add the spell, too) and speaking with dead, and Life Magic might be about animating dead and resurrection.
If you're playing solo, I feel like you should only think of it as "cheating" if you personally feel you're getting robbed of interesting play. There's no need to hold yourself to any more objective standard than that, in my opinion.
RE: magic styles, it is definitely loosey goosey in the book. A thing I tended to do was give a style fewer spells if the style gave access to what I thought of as more generally useful or potent spells, and give a style more spells if they were very situational. If commanding undead seems like it would come up a lot in your game, separating the two ideas like I mentioned above might be a good idea. If it's more niche, just make it one style. Again though, you should really only worry about changing this if you feel it makes the game too easy for you to make any fun decisions.