Wrestlers are not underpowered. They are however more realistic.
Axe>hand.
Other forms of damage are a little underpowered, but Wrestling should be amazingly useless.
Though I appear to be the exception. all my wrestlers have figured out the art of cutting their opponents with the enviroment. I keep finding trog blood all over from my legendary wrestler.
Another reason Wrestlers suck now is they no longer are invulnerable to attacks now that Dodging is part of the Dodger skill instead of Wrestler.
Mmmm, Weapon fighting vs Wrestling: Large weapons, like axes, longswords, maces, spears, whips, and crossbows... Are very easy to disarm or at very least disable. So an excellent wrestler with good enough agility has a reasonable chance of defeating a large weapon opponent. Wrestlers with enough skill should be able to break limbs and apply chokes, however, it would take much more time to kill an opponent than with pretty much any weapon, so if there is more than 1 opponent the wrestler gets tied up with 1, and killed by the other.
Striking should be less useful against any type of weapon, but potentially more useful against multiple weak opponents, and about on par with wrestling (if the wrestler attacks a striker neither has a clear advantage).
Small weapons, short sworts and daggers, should dominate wrestlers, and edge out strikers, but lose to most large weapons (unless it's used in conjunction with wrestling, disarm the large weapon opponent and THEN stab them). Small weapons are extremely difficult to disarm without getting seriously hurt, but of course, they don't have the damage potential or range of a large weapon.