Shield spells for alteration are very useful. All those 'stoneflesh' and such spells are a good spell to have. And I think you mean the wikis seem to 'lack' a lot of info, and not leak?

As for illusion, it's completely focused on making opponents frenzy against eachother, calm some others and maybe even command some of them, iirc.
I know there was a lot of trivial spells in Morrowind, but I can't help but miss them from time to time

As for the miss spelling, I am aware. Its some sort of writing disorder, I can't really help it, and notice it, unless I write something done, leave the text for a good few hours (so I don't know it by heart) then re-read it. Trust me a small is nothing, it can be much much worse unfortunetly :/