Do these percents match up to what you would expect? This is a fully buffed x vs y in a party situation (as many buffs as can be shared, etc).
(F)ighter, (W)izard, (C)leric, (R)ogue
So a fighter that is going toe to toe with another fighter would have a 40% chance to hit with each strike. This does not account for touch attack specials which everyone will have access to (to probably hit a 60-70% hit chance rate). This accounts for typical feats (attack with the best set of feats/skills/buffs vs defender with best set of defensive feats, buffs, skills).
It does NOT include combat expertise or any other mode which could modify it further (and is available to all classes). This is a basic spy vs spy thing to make sure the core game is balanced.
F vs F 40
F vs W 35
F vs C 35
F vs R 35
W vs F 25
W vs W 20
W vs C 20
W vs R 20
C vs F 40
C vs W 35
C vs C 35
C vs R 35
R vs F 30
R vs W 25
R vs C 25
R vs R 25