Upper_Krust
Legend
Hey Seasong mate! 
I would have all armor and shields and all simple and martial weapons at +0.4. (total)
If you try and do it for every individual level you will only end up bogged down in a world of hurt.

seasong said:So, I was playing with classes and CRs again, and I realized what was bothering me.
Upper_Krust averages the CR bonus of all levels for expedient math. At 20th level, the Fighter (with no racial bonuses) is CR 20.26, spot on. But at first level, he's CR 2.455.
0.3 - d10 HD*
0.15 - BAB +1
0.125 - Fort +2
0.2 - base character feat
0.2 - bonus fighter feat
0.08 - 8 skill points
0.8 - all armors and shields
0.4 - all simple and martial weapons**
0.2 - level 1 wealth
* this does not account for the max 1st HD rule.
** technically, a single weapon is a feat, but in practice, "all simple weapons" is no better than "one good simple weapon".
I would have all armor and shields and all simple and martial weapons at +0.4. (total)
seasong said:Anyway, for simplicity sake, it's not generally worth worrying about - at the low levels, a little extra survivability's not a bad thing, and it all washes out at the higher levels. But it was what was bugging me.
If you try and do it for every individual level you will only end up bogged down in a world of hurt.