[68c12c16]

I feel another place in Measure for Measure that also indicates the depth and the subtlety of Angelo's character is that his monologue in Act II Scene IV,

  When I would pray and think, I think and pray
  To several subjects. Heaven hath my empty words;
  Whilst my invention, hearing not my tongue,
  Anchors on Isabel: Heaven in my mouth,
  As if I did but only chew his name;
  And in my heart the strong and swelling evil
  Of my conception. The state, whereon I studied
  Is like a good thing, being often read,
  Grown fear'd and tedious; yea, my gravity,
  Wherein--let no man hear me--I take pride,
  Could I with boot change for an idle plume,
  Which the air beats for vain. O place, O form,
  How often dost thou with thy case, thy habit,
  Wrench awe from fools and tie the wiser souls
  To thy false seeming! Blood, thou art blood:
  Let's write good angel on the devil's horn:
  'Tis not the devil's crest.

Clearly, Angelo feels a certain conflict in his heart, and he struggles hard with this cognitive dissonance, which shows that he is not utterly evil.

  And there's a lot of that in Milton's Satan too. He's   
  undeniably colourful, but seriously, complaining to his
  companions how crappy it is to reigned over while at the 
  same time declaring his own ambition to reign over them.

I am not that sure to what extent this reign is over them; and who those "them" are? It might not necessarily mean his fellow fallen angels but those dead souls in hell...

And also, he is having a conference with his comrades in Pandæmonium, right? In this sense, his power over his comrades -- if he is superior -- is not absolute, as at least he consults them, unlike that in heaven...

[mrec]

> which shows that he is not utterly evil

Oh, no, I certainly wasn't suggesting that. If you squint a bit you can almost see Angelo as a tragic hero undone by his own virtues; piety and self-restraint have always come so naturally to him that he's never had to build up the moral muscle required to resist temptation. So when he does fall, he falls hard.

> I am not that sure to what extent this reign is over them; and who those "them" are?

A good point.