Not including the Admirals or Blackbeard due to that being unfair, as well as leaving out most of the mediocre henchmen, then something like:
Top Tier
Enel (Arc Maxim Deathpiea)
Crocodile (Marineford)
Lower Top Tier
Magellan
Enel (200,000,000 Volt Amaru)
Enel (Raigo)
Upper High Tier
Shadow Asgard Moriah
Kuma
Moriah + Oars
Oars
High Tier
Pacifista
Base Enel
Leopard Hybrid Lucci (Rokuogan)
Base Moriah
Leopard Hybrid Lucci
Mid Tier
Base Lucci
Alabasta Crocodile
Arlong (Water)
Low Tier
Arlong
Kuro
Krieg
Wapol
Buggy
Slim Alvida
Bottom Tier
Morgan
Foxy
Fat Alvida
Note that Enel's placement has more to do with his massive attack power than his poor durability, since durability isn't much of a factor in this ranking when the only other East Blue villain with any Haki knowledge is arguably Crocodile and even that isn't a fact.