He is lacking crit, or attack speed to get something from his power. There is no escape mechanic built in what so ever. No range weapon makes you fodder for gas, storm and any kind of special that can attack you from afar without you being able to reach it, like a leech on a ledge, and he lacks any kind of meaningful mitigation since Stoicism (aka straight up horrible version of oblivious to pain) is just a weird joke when most of your damage is from specials, AoEs and your Blessed Sword not letting you block instantly after executing it. His monster damage is not half of what Shade is able to pull off even with Audacity and Confidence has a maximum amount of targets, after which it deals no more damage, which makes it annoying to get Elites from waves at times you really need and want to.
In terms of close combat killing power he lacks far behind WHC, Shade, Zealot and Slayer, while having no access to a range weapon. His passive group support also is random, while not getting close to what a WHC has to offer at all times.
He is fun because he is new, but once that shine vanished there is nothing left that makes him stand out from any other class. Reworking Stoicism, giving him a bit of DR and taking a look at the Blessed Sword in terms of damage and/or the openings you have to suffer using it might make him a decent career. (Also the Day 1 bug of Knightly Temper kills not granting THP on Kill is rather annoying.)