In my opinion, most of the ones in Our World are way overstatted. I'd say 'low level' Denarians should come in in the low teens refresh, 'middling' types in the neighborhood of -15, and ones like Ursiel and Tessa in the high teens to low twenties (my version of Tessa would be -21, I think). Only Nicodemus is really plot device level, IMO.
I'd say the basic Denarian template should include Beast Change, Demonic Co Pilot, Supernatural Recovery, and Hellfire if you're already a spellcaster. Everything else should be individual, though most will have a lot of other powers: spellcasting, Speed, Strength, Toughness, etc.
For example, a muscle type like Obsidian Statue might have these powers:
Beast Change [-1]
Demonic Co-pilot [-1]
Supernatural Recovery [-4]
Inhuman Toughness [-2]
Supernatural Strength [-4]
A weaker spellcaster type like Rosanna might have:
Beast Change [-1]
Demonic Co-pilot [-1]
Supernatural Recovery [-4]
Evocation [-3]
Thaumaturgy [-3]
Sponsored Magic, Hellfire [-2]
Note that Tessa is called out (in SmF, I believe) as unusual among the Denarians for being probably White Council level! They do not tend to be magical heavyweights.