Not until they sort out the Radiant Servant fix and release it, so it's not the shining time for Radiant Servant, yet. Currently it works out best with offensive casting type cleric, but not for melee type.
To be more accurately, been a radiant servant require some extra odd action point cost beside Empower Healing feat; Cleric Heal II (for 3 AP, yeap, please inspired me whoever pick those up before the release of Radiant Servant
), Improved Turning I (for 1 extra AP, again, most people are hardly fans of this odd enhancement); Furthermore, for those whom never take Divine X enhancement before (like most of my cleric), they have to invest at least one rank of those enhancement (so it's 1 extra AP).
So the true cost of Radiant Sarvent for ordinary cleric is one feat and 9 AP. Anyway, it's very useful and powerful for many type of cleric, but certainly not include melee type at the moment.
Rank II Radiant Sarvent is another story. If one never pick up deity line enhancement up to rank II or Cleric Charisma II before, she / he must spend up to 6 extra AP before she / he been able to purchase Radiant Sarvent. So the true cost could be up to 8 AP (include the RS II) to gain access Radiant Sarvent II. Is it worth it? well, it really depend on how much Empowered Healing casting are you going to use on a daily basis (but the benefit of RS II certainly encourage people using it -- well, obviously, I didn't mean the Positive Energy Burst
). If one doesn't make use of high charisma, Sovereign Host was one of the better choice, IMO. (Their rank II give a special heal ability once per 10 minutes)