Let's be honest, that's what we care about when choosing shields. If the shield actually has, you know, the ability to shield something, that's a bonus.
Here's how I'd distribute them!
Barbarous Thorn Shield: Keeps sword damage +2. Freeze/Poison resistance. We need a freeze/pierce shield.
Crest of Almire: Sword speed +2
Heater Shield: Sword CTR +2
Ironmight Plate: Bomb damage +2
Volcanic Plate: Bomb CTR +2
Gray Owlite: Handgun CTR +2
Dread Skelly: Handgun damage +2
Royal Jelly: Handgun speed +2
Dragon Scale: MSI +1
Aegis: Universal damage +1
Ancient Plate: Universal CTR +1
Omega Shell: Health +6 (previously suggested +4)
However, I demand that Omega shell get +6 health.