Aasimon: Seraphim, Cherubim, Dominions (d20 Apocalypse)
Gotthammer (Avenging Angel) (Urban Arcana)
Feinds, General: Rotlord (carrion feind) (d20 Modern CRB) (maybe a Yugoloth)
Demonic Machine, Harriken (headsnatcher feind), Murdergaunt (Whistling Fiend), Luciferan (Menace Manual)
Demons, General: Demonic Auto (Urban Arcana)
Baatezu: Baal, unique archfeind (Menace Manual)
Tanarri: Festergog (vomit feind), Skinhusker (blade feind) (d20 Modern CRB)
Fleshraker (knife feind), Jumping Jack (blood feind), Kwevencha (Spider Fiend), Stygilor (Tumor Fiend) (Menace Manual)
Naberus (cacophonous feind), Marchocias (bull feind), Belphegor (ravenous feind), Apocalypse Demon (template) (d20 Apocalypse)
Shock Feind (here)
Platonics: Sraosha (Platonic of Contract Enforcement) (Urban Arcana) (each Platonic represents a particular concept, rather than a particular alignment, like most Exemplars do)
Vivilors: 1st-level Vivilor, 2nd-level Vivilor, 3rd-level Vivilor, 4th-level Vivilor, 5th-level Vivilor (basically, Astral Constructs for arcane casters, probably from Limbo) (Urban Arcana)
Etherial Plane: Dimensional Horror (Menace Manual)
Mothfolk (menace manual)
Horsemen of the Apocalypse (d20 Apocalypse)- note, these guys are True Neutral.
Tell me if I missed any.
Since the beliefs changed, some new outsiders probably evolved but spend most of their time in their home planes, so they went unnoticed by those nice people collecting creatures for menace manual
I have just a few ideas for now and they might seem like disney gone psycho, but here they are just to get a ball rolling:
Hedgefrog
An undoubtably evil creature is usually found jumping around roads and highways connected to the lower planes, hedgefrog looks like a thickly armored armadillo with a few sharp blades extruding from it's body. It's sole purpose is punishing the speeders by jumping under the car tires to puncture them.
They avoid combat ac much as possible and plane-shift back home the first chance they get, but they can be dangerous when cornered
Dust bunnies
These smelly creatures from the elemental plane of dust usually follow larger creatures that stalk people from under their beds. Most of them are too weak to fight on their own, but they provide excellent support with their abilities to jump, glide (or in some cases fly) and choke people with their own bodies. When the leading creature of their choice gets caught or killed, they flee in panic