The Luminous Shroud displays an increased regen of 10hp/s /charge, although it does not do so in reality (still 16.7hp/s).
A shroud dropped for me in my NSE run (from a dreaming nomad) relatively early on in the Outer Realm. Even with my Manticore, it's 1242hp (1350hp on other ships) / 15.6hp/s regen at +130% (molbidium + 12x diamond field crystals).... which is like a Mammoth version of the Iocrym cocoon, but at 160MW. i.e. I've gotten my endgame shield before Dantalion... and before completing PJ (skipped ahead to find a fabricator for Heavy Launcher missiles)
For reference, at its base stats, it's better than a Jotun at 280MW, and it's ~92% stronger with 4 charges. Sure, the Jotun is pretty underpowered and needs a buff, but this is quite overpowered.
Perhaps a way to avoid such stacking would be to increase the shield +%HP / attempt to enhance the shield further up to +80% (kind of like using another field crystal), i.e. it'd be a shield that would be easy to get up to +150% without going out of your way to find/order diamond field crystals? (Alternatively, give it resistances, kind of like Luminous drones, but stacking (e.g. +blast/+particle/+ion/+thermo)