That One D&D version does sound more generally useful as well as more fun thematically. Though competition for concentration might still be an issue that makes it less useful?
The One D&D version does still suffer from concentration, making it ~useless to cast on yourself especially now that you'll have less AC = hit more often. It'd be much more appropriate for buffing others (Barkskin on a Raging Barbarian so they regain 6 hp each turn while only taking half damage!!!)
