I think, in a recent thread, Raze posted some formula for Armor.
It must have been tons of work to get XP data.
Getting the data I took was only starting a new game with changed stats of some 30 or 31 swords that I had conveniently placed on Cyseal Beach where players start after char creation ;-)
... and the big surprise for D:OS2 will be: published formulas ... ;-)
If my math classes hadn't been so long ago, I might have figured out the damage formula which is used for both weapons and spells.
Now I'm too lazy to 'find the pattern' ;-)
I had always relied on some formula posted on some D:OS wiki before, but with the data, it wurned out that it must be wrong because it was only close for low levels/low damage values.
I used the data in my attempt to minimize the damage difference between weapon types in XC_Bags.