What i miss in Life splinter is a proper self heal monster (besides the legendary unicorn...), with a defensive skillset, therefor my card would be:
Name: Ascetic Warpriest
Splinter: Life
Rarity: Rare
Mana: 8
Attack: Magic 1-3
HP: 9-12
Speed: 1-3
Armor: 0
Skills: (1)Heal (5)Soul protection (Take the HP damage instead of the adjacent monsters) (8)Life leech