Visual cues for where to shoot things

Somewhat related to my other post, but a different question.

Is there a visual cue as to where I should be shooting things? In Borderlands it was usually clear. Shoot people in the head, and other things where they didn’t have obvious armor. (and you could easily see the crits and damage done) With many of the enemies in this game, I don’t see clear shoot locations. For example ISIC. I realize you shoot his power bar thingies when they are open, but where do I shoot him?

I think the reason I’m not enjoying the game is I have no idea what I should be doing most of the time.

Look for visual queues in a character. Do they have a piece of their body that is breifly exposed then covered up? Clearly a weakness? Does it glow or do they attack from there? A weakness.