Originally Posted by Pechvarry
I think this is a pretty neat concept, but I don't quite like the implementation. Call me a Tier 4-and-pretends-ability-damage-doesn't-exist kind of guy, but I think I'd rather keep the ACs as they are, in addition to having armors grant a simple (Armor bonus) temp HP/round, so a +5 Full Plate gives 13 hp/round. Just something to take the edge off being in the front.
I could see the amount doubling for each iterative attack you possess from BAB (I love gating abilities with BAB and banning Divine Power), so a +1 Breast Plate which gives 6 temp HP at level 5 would increase to 12 temp HP at level 6. And the 13 armor Full Plate gives 52 temp HP/turn at 16 BAB. Still not as huge as your numbers, but also provides AC.
This is a reasonable alternative, particularly with the BAB scaling. The only thing is I was imagining it more along the lines of the heavy armor wearer gets hit more often, but takes less damage. With your suggestion, Heavy Armor gets hit both less often and takes less damage. This may not be a bad thing (as I do think heavy armor, being a harder to get proficiency SHOULD mean something), but it is an important point to consider. Light/non-armor wearers under this system wouldn't be just have higher attribute requirements, but would be substantially squishier even with good attributes, than their heavy armor counter parts.
Also, this does make converting monsters a little trickier, they (mostly) don't get bonus attacks from BAB, but instead from extra natural attacks. Would you make it still scale with itteratives (making monsters a little weaker since they don't get them), based on natural attacks, or based on BAB regardless of iteratives?