Well, there's the Economic Overlay, which has always been there. It shows mass/power use of every building and unit, but it's rather cumbersome to figure out power problems from that.
Supreme Economy Next is a mod that shows your top power draws/mass draws. You can click on the avatars and it will select the units involved.
UI Party gives graphs of different categories, such as Radars, Shields, Mass Extractors, T2 Unit production, etc. Each is further divided into Using vs Building. Click on the U or B box to select the units involved.
UI Party also has a great deal of other features, some of which are bugged or incompatible with the latest FAF version. If you decide to use it, disable the 'Select Similar Assisters' and 'Unit Lock' features (via the UI Party menu, the little wrench icon). Those seem to be the source of the bugs.
T2 Fighter Bombers (Notha's) on patrol. They repeatedly flew over an enemy T3 MEX and didn't attack it.