Unified Tables of Combat Stats

[Aulirophile]

AC

Defender: Level+18 AC
Other: Level+16 AC

NADs

Defender: Level+16
Other: Level+14

There you go. This will vary somewhat, Str/Con defenders will have terrible Ref and Will but they usually have some other mechanic (Font of Life, constant THP generation, etc.,) to help deal with it. Worth noting that some games give out the Epic NAD feat to the lowest defense each character has, and then ban taking them. I personally do this when I DM and it keeps defenses much more even. Also Improved Defenses has evened things up considerably.

 

[Jhaelen]

Have your players give you copies of their character sheets every time they level up. Then you can see exactly what stats the PCs have, and plans your encounters accordingly.

To be honest, as a DM I rather enjoy being surprised by my players from time to time. It's only fair since _I_ get to surprise _them_ fairly regularly

My approach to designing encounters is to vary them as much as possible and just throw them at them to see how they cope with them. This results in some encounters being (too) easy, others being (too) hard and the rest being about right. IOW: Exactly how I like it.