Blind would cool if it was effective enough to be worth casting.
Sanctuary could be good if they explain why it's an illusion spell. In Morrowind, as I recall, it just did make the target more difficult to hit. As if he was occasionally ephemeral. Perhaps it works by making people think the target is a foot or so away from his true position. I think a blinding cloak or area on effect spell could cover both of these.
I'm not that fussed about chameleon because the subject still has to be very sneaky and its adavantage since Morrowind of not deactivating as a result of interaction just takes away the strategy.
Charm needs an extensive persuasion system. If it does come back, I'd like it to be cast in dialogue, not by slinging ball of light at the target. Perhaps with a chance of failure and getting caught.
Sound isn't much use when spell failure doesn't exist. Diverting sounds like thrown voices and footsteps are another matter.
Having fury and frenzy is like carrying around flame cloak scrolls and J'zargo's flame cloak scrolls.
The obvious way paralyse a target is physical or biological, not mental. It certainly shouldn't be exclusive to illusion.
I'm not interesting in seeing silence (i.e. prevent spell casting) come back as an illusion spell until we get some more lore about incantations. I wasn't expecting any, but a book in Dragonborn briefly discusses spell casting technique so there's hope yet. It would have made a good mysticism spell before. Now I suppose it would be alteration.
That would be good so long as the npc's were programmed to notice it reasonably quickly. When one sees a mage summon a daedroth, chances are, he's summoned a daedroth, but the player character wouldn't be first person to summon a fake daedroth.
Altering it to what though? Maybe it could be cast at a target and the target's race and apparel (e.g. clothing value range, faction specific armour) would be taken into account.
I think he's saying it's boring, not underpowered.