you really need to read up on pally builds talon.
AC is a matter of gear in this game, and with very few exceptions for a couple of AC not based on class anymore. check the AC threads.
pallys do ENORMOUS damage. Divine Might is ridiculous. Exalted Smites are ridiculous. Divine Sacrafice is Ridiclous.
You can pretty much hit ES or DS anytime you know you need a crit (in my case dualing rapiers on a drow pally) and banish/smite/dual ES crit (dps) whatever you want.
its hard to make a good pally, its nothing close to impossible.