To be honest, I'm not that impressed with the Iconic Past Life feats, especially the Sunelf.
But there is one thing that might spark my interest in doing Iconic TRs: allowing me to pick the first level class from creation. I'm not suggestion that a single Iconic TR unlocks it for all Iconics, just the one that matches the Past life feat.
For example, by gaining the Bladeforged past life feat, players will no longer be locked into the Paladin class anymore. However, if the same character choices to be a Purple Dragon Knight, they must start as a Fighter until they gain the Purple Dragon Knight past life feat.
I think players may be more receptive to Iconic TRing if this happens. Right now, there's little to be gained in Iconic TRing, especially with the high cost in COV and XP.