So I am currently playing a pure Vampire Lord character and I was wondering what all the upgrades to the vampire form in terms of items and artifacts were exactly (Not Perk tree Related!)

I know there is the 2 amulets and 2 rings, and I have heard that wearing Harkons armor carrier over its enchantment to the Vampire Lord Form. Is there any other items that do this and also which combination of the amulets and rings do you think is the best?

Also by doing side quests for retrieving items you can upgrade the longevity of the Bloodstone Chalice, what is the maximum upgrade time for it and is there any upgrade that also upgrades the effect as well as the longevity?

Oh and I would also like to ask what do people think of the Vampire Lord form? Overpowered or not? ect ect