There is nothing inherently wrong in having a material providing a concentration/animal empathy bonus. On the contrary, they were chosen precisely to offer variety for armors. Even if you do not use animal empathy yourself, the +2/+4 bonus to concentration remains useful enough to any spellcaster. Not everything has to be optimal for everyone, it is proper that players be forced to make choices, and changing the bonuses would negatively impact some other players as well.
Noted.
But just to restate its not about being optimal, just that animal empathy is literally unusable by all but two classes.
Dire elephant hide however being the only source of concentration, still makes it a good choice even though the AE bonus is
dead weight.
That being said, i do agree now that it is for the best if the current hides do not get altered as to not negatively affect other players.
...I was thinking maybe Discipline now that it is no longer offered as an enchantment bonus on armors...
I might make myself unpopular with this opinion, but i don't think adding a leather material with discipline is a good idea.
You already get a +5 discipline bonus on enchanted plated boots/gloves, adding another +4 or +5 from lining on top of that would make for some ludicrous bonus.
For alternative suggestions to hippo hide properties;
Concentration + Spellcraft (nearly hairless, probably makes for good vellum scribing)
Concentration + Antagonize (they're stupidly aggressive)
Concentration + Saves vs Disease (their blood-sweat has antimicrobial properties)
Those are some solid suggestions.
would also love to see hippos in game in general, in Markovia at the river and in Har'Akir at the oasis, now that they don't look like 3 polygon eldritch horrors anymore.