My issues with ice armor are well documented in these forums and this post is not meant to re-hash those. I think that absorb spells have uses (especially now that the ward elevator routines work correctly and consistently), however, I still struggle with ice armor. It is the only trained spell in the game that is literally completely replaced by a new spell. To be sure, other schools get upgrades that make old spells feel obsolete. However, ice armor is the only one that is completely replaced. Consider Fire's link spell. Fire gets power link later on in the game and in most respects it is a better spell. However, there is still a place for link in the game because it is only 2 pips vs. power link's 4. That fundamental pip difference makes it useful in different situations than power link.
Ice armor, on the other hand, is literally a "rip and replace" spell. Both ice armor and frozen armor are X spells so they will always use the same number of pips. While ice armor is "self only", 90% accuracy, and 125 absorb points per pip, frozen armor is for anyone, 100% accuracy, and 175 absorb points per pip. I suppose its possible that they might stack, maybe... but what would the point be in that? Healing is actually more pip efficient, absorbs can be pierced (with the spell, not armor piercing) away for 0 pips, quaked off, stolen for 2 pips, or just simply ignored by steal spells. Don't get me wrong, they have some tactical value, just not enough to bother trying to stack them.
With absorbs you can protect shields from small damage spells such as fire elf and wand hits. You can insulate traps to prevent them from realizing full damage potential. You can drop them on your low health minion to prevent it from being wiped out immediately by AoE spells. They are also immune to armor piercing. However, there is no reason at all for ice armor after you acquire frozen armor. In the past, I suggested that ice armor casts a taunt proportional to the number of pips used on the armor but as I was thinking about it again, I would like to suggest something else. I would like to suggest that ice armor have a pip cap like Myth X minion spells. If the most you could put in it was say, 4-6 pips, then it would be useful for the tactical reasons above without exhausting all your pips. This change would be enough of a difference to make it useful in situations where frozen armor is not. Please consider limiting ice armor to either 4 or 6 pips.
I look forward to any feedback, questions, or suggestions on this proposed change.