Base Defense Bonus + Armor as DR, Alternative Rules

[Archaos]

Hey everyone.

In our campaign we're playing basically vanilla Core in the Realms, except for a few things.

We're using a couple alternative rules such as Base Defense Bonus (AC that goes up as you level up like BAB) and using Armor as DR. Not shields or magic bonuses to armor though (such as Shield of Faith, Barkskin, Shields etc.)

Our party is a Halfling Rogue, Oghma Cleric and my fairly optimized Snow Elven Druid (Cha penalty).
Though by optimized I mean that I know how to play a Druid and reading the Druid's Handbook all the time.

What do you guys think about those two alternative rules? Do they improve gameplay? Make it more interesting and realistic?
For one, It improves the AC of my animal forms at least.

[OldTrees1]

Given a few exceptions (ex: 4th level Cleric in Fullplate), each character will get more AC and a tiny (possibly insignificant) DR.

Since it is easier to boost Attack than it is to boost AC, systemic boosts to AC are beneficial.

[Archaos]

I forgot to mention. Enemies get the same benefit as well. Not just the party.