Currently, life recovery is a pretty rare perk. This could help and make it more present. Also Life recovery works very well with healing mantles like Octans, Aevitas, and Fornax. Being able to focus life recovery with armor could make for more interesting builds with these mantles. Personally, I feel like Bootes would be the most fitting constellation since it is sorta life themed and is currently just a worse version of Aevitas for armor (+2 added life vs +3 added life), but if another constellation fits more, so be it.