You think it would just make the cleric obsolete? There would be no need for downtime anymore because the char would just stand in the campfire for a few hours and bam, full hitpoints. Then he passes the ring to his buddy to do the same. When doing a dungeon crawl, he just holds the torch to his chest or arm so even when he is not fighting someone with fire ablitiy he can maintain fast healing. I agree with nifft in the fact that healing should be harder than harming.