I'm going to scale the neptunic shark suit to about 15 hitpoints.
It's one of the best achievements of modern armor, tested to be able to take the force from the jaws of a full sized shark while ensuring the human underneath remains intact, and provides top to toe protection.
It is probably bullet resistant, but I doubt it handles sustained rifle fire very well.
This abomination, the Brewster Armor, is proven be both man-portable and impervious to rifle fire. It weighs 50 Kilos. If I didn't have to do prolonged marching to reach a gunfight, I'd wear this. (unless I get shot at by tanks)
This pervert suit also looks really good, and we could use it to model a stripped down version of the Brewster armor.
This armor was mass produced,
probably half the weight of the Brewster Armor, it was about 10kg. but was proof against rifle fire only at 60 metres and further. It was made from nickel-steel. If one were to scale this up with a blank cheque, I would try the same design with modern superalloys like nickel-nobium
Pic of some Lobster armor after being shot at:
This fancy armor is also made by the Germans for officers. But there's less data on people shooting at it.
The German Lobster Trench Suit and the Brewster Suit were used by the Germans and Americans in combat, and both are proven armors.
But the thing is, modern rifle plates and vest carriers have shit coverage, and casualties from people wearing them are mostly from bullets and shrapnel going in through the gaps. If you can sacrifice mobility, you can go full retard with the armor even without an exoskeleton.
Some other pics I found:
Italian WW1 soldiers using body shields on the march:
Use of a hand shield in WW1: