| Dayr |
I agree that to some extent there's no reason anyone would ever take banded mail if full plate is available. I'd rationalized that as "some armors are just better than others," but on reflection it might be nice to give some love to plain leather armor. Either armor proficiencies would have to be drastically overhauled (ugh) or the max dex and armor check penalty system would need to be more extreme. Dunno.
This is the point I'm trying to address. The whole "some armors are better than others" is one I don't initially agree with but I'm open to some discussion on the matter. In a perfect system I'd have all armors have strengths and weaknesses while ultimately being roughly equivalent.
In your example banded mail while less comprehensive in its coverage (lower AC) than full plate makes up for it with is drastically higher maneuverability (higher max DEX and lower ACP). But at the end of these differences rarely matter when to fully benefit from a higher max Dex bonus (easily the most heavily weighted attribute) you must spend vital resources to keep banded mail equivalent to full plate (whose full benefit only requires the actual cost of the armor itself). Not to mention the fact that most of the rules concerning the limiting of the usefulness of heavier armors (low mobility, exceedingly long "prep" time) can and will be hand-waived for the sake of expediency.
Again I'm stumped as to where to go with this solution but as always the most elegant solution is generally the simplest as well.
Regarding armor as DR, that would entail reworking all of the DR options sprinkled liberally throughout the houserules (armor training talent, barbarian class feature, most 3rd level sorcerer bloodline powers...), which is something I'd hate to have to go back and undo.
Again, as this is likely a knee jerk reaction on my part I hadn't fully thought out the consequences of adding in the DR rules. I have to wonder though if letting the armor DR stack with your other DR options you've mentioned would be truly unbalancing. If anything it's at most an extra 4 DR on top of your options and on the other hand it’s simply yet another option you have to allow your players to create the characters they envision.