Armor with hit points, at least a simple version, is a pretty decent way to handle it
IF you want: A) Some form of armor DR,
AND B) A simple way to handle damage/repairs to armor. If you want both of those things, now you've got both of them wrapped up in one simple package.
OTOH, if you only want DR or only want repair, that's not necessarily the best choice. And certainly if you don't care about either, then it's just extra, unnecessary baggage compared to the standard D&D way.
So a simple rule that keeps the AC values of armor lower and/or even not present in return for each armor giving hit points, is a great optional rule. Keep it simple, and you don't even need to change anything else. Just specify in the rule what it implies.
The main problem with the usual armor DR schemes (in many games, including D&D)--such as DR 4 eliminating the first 4 points of each hit--is that they imply a lot of armor reducing hits to no appreciable damage. This usually slows down the game, skews balance, doesn't do much against mega attacks, and certainly doesn't fit the typical D&D framework. Hordes of kobolds lose all threat, unless you put in a lot of supplemental rules for grappling, bypassing armor, etc., which just compounds the problems. The next choice is usually DR as a slight percentage, with the usual problem of lots of fiddly handling.
So I've thought that if they wanted a straight DR option, a good one would be to give each piece of armor a DR that doesn't kick in until N amount of damage, and set N high enough that it doesn't apply to most average attacks. Then let the armor knock out a pretty good chunk of points, then fail to prevent any further damage. So if ringmail stops the first 10 points of damage over 12, that's really nice when you are getting pounded by ogres. It's pretty useless against 20 archers turning you into their private pin cushion. And for giants, big dragons, and the like, it turns into effectively standard DR, since they are nearly always hitting for more than 22. A similar option would be half damage up to X damage threshold, with a minimum of 1 for each hit. Tougher armors have a higher threshold, but the mechanic is always half, which is easy math.
Of course, with the way Next is doing bounded accuracy, but letting hit points and damage values scale, you could also do some pretty neat things with letting armor knock a die or two of damage off of higher damage attacks. Plate--for any attack that does 3 or more dice of damage, drop the highest damage die rolled. For any attack that does 7 or more dice of damage, drop the two highest. And so forth. This obviously works better for groups that roll damage out in the open, as the plate guy gets to feel really good about taking those dice out before totaling the amount.
