Yes, a lot of people seem to dislike the fact that untargetable creatures truly are untargetable, for that reason they already made shields like Fire Shield and Thorn Carapace affect immaterial creatures, and when using untargetableness (like Quintessence), you'll find out it only works well against decks relying on creature control, and that Quintessence is just a dead card that prevents you from targetting them yourself (blessings, reverse time) otherwise.
I doubt delaying buffs is the answer, some creatures are so fragile yet hated, that they are practically useless without immortality, so I'm afraid I'd have to say I'm against this idea.