One of the main problem of Two-handed flails – is too much damage spread, espesially for top tier ones.
I suggest increasing the minimum damage of the best two-handed flail to 50-55. Then it will be more stable and usable. I also propose to change the rather strange and random mechanics of the stun at the two-handed flail to 100% Daze when hitting the head, it will be more stable and will work even for those who are immune to stun.
"Death is a part of mercenaries job."