At 19th level, the radiant avenger gains access to two additional daily attack powers, including the following somewhat more complex daily battle blessing.
Blessing of Recovery
Paladin Attack
Daily * Divine, Stance
Minor Action
Personal
Effect: You invoke the blessing of recovery. Until it ends, when you hit an enemy with a weapon basic attack, you may make a saving throw and you may choose to either deal additional radiant damage equal to your Charisma modifier or regain hit points equal to your Charisma modifier. In addition, when you use a divine power with the radiant keyword, you may make a saving throw. Until the end of the encounter, you may re-invoke this blessing as a minor action.
If you use smite of radiance while this blessing is invoked, you may forgo the additional saving throw you would gain from using the power to gain a power bonus equal to your Charisma modifier to the saving throw you gained from the weapon basic attack.
If you use pulse of radiance while this blessing is invoked, each ally in the burst may also make a saving throw.
EDIT: I tweaked the wording of the power slightly to grant a saving throw every time the radiant avenger hits with a weapon basic attack, regardless of whether or not he chooses to deal additional radiant damage or regain hit points. I also re-worded the benefits for using
smite of radiance and
pulse of radiance since they would each technically grant the radiant avenger a saving throw when used. This means that a radiant avenger could actually get two saving throws out of using
smite of radiance after hitting with a weapon basic attack while this blessing is invoked, or he could go for a single saving throw with a bonus instead.