Did you check out Matthew's points in the comments? I like his ideas, though I'd be inclined to bump his suggested +1s to +2s, because I agree with Delta that +1 bonuses are a little too small and fiddly to really bother with.
Who is Matthew?? I see an Unknown, is that him? If so, the +1's on a d6 would have to be at least +2 on a d20...
Otherwise I am not sure what you are talking about...
Anyway, a lot just depends on how fiddly a system you want. In our 5E MOD, AC works normally, and offers DR, but only against critical damage (a la d20 SW sort of).
I've also toyed with halving the AC bonus for Armor (round up) and using the other half (round down) for DR.
So, leather AC 11 would still be AC 11, no DR
Studded Leather/Hide would be AC 11, DR 1
Chain shirt would be AC 12, DR 1
...
Chain mail would be AC 13, DR 3
Splint would be AC 14, DR 3
Plate would be AC 14, DR 4
Then allow full DEX regardless of armor worn. This way, you want STR for heavier armor, so it is unlikely you will have a huge DEX, and vice versa. It works best if you use the variant encumbrance system and not the default however.
Shields are AC +2, but you can use your reaction to get DR 2 (block), then the DR drops to 1. Use it again and the shield needs repair, AC becomes just +1 until fixed and no DR. If the damage it absorbs is critical, it is destroyed and cannot be repaired.