I agree with you again, but there are three extremely powerful normal weapons in the game, the 3 Great Cleavers.
They start as +1 weapons, counts as Hand Axe for Wpn:focus purposes, wielded one handed and has 1d10 dmg, threat 17-20 x3.
According to your above post Keen should make them threat at 13-20 and Improved Crit:Hand Axe make them threat at 9-20.
BTW they CAN be enchanted with keen, already done that.
Threating a crit at 9-20 is over 50 %, and in the hands of a rouge this is way too powerful IMO. I made a rouge3/ftr7 just to exploit this weapon and its awesome

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My favorite Great Cleaver is now +3, holy, axiomatic, icy burst, shocking and is by far the weapon that deals the most damage, much better than the Scather/Fragarach swords except for the "always hit" part.
My rouge has a normal light hand axe, (similary enchanted) in the off-hand. Imagine utilizing all 3 Cleavers ? True powergaming IMO.
While flanking you will hit most of the time.
Just a thought...
Have Fun
