RE: CSC advanced TLs - Yes there is very little detail... you are, after all, intentionally designing something outside the setting's nominal max TL.
This means there are no 'standard' stats - each design can be different and yet still be compatible with official material by using only the tech listed, or applying other penalties (as in the 'riskier' AM power plant) based on the exceptional TL.
Regards using AM in the quality minded culture - your call - of course, I would assume they would have backup PP anyway.
As to the black globe - it should be gleamed from the rules that they are primarily intended in a defensive posture. During combat they provide extra armour in flicker mode (and capacitors are easily added plus the jump ones - for ships of equivalent scale this is well done). They also defend against all weapons (like mesons) - something other tech can't do by themselves.
The full black globe mode is balanced by largely being desirable only before combat and sensor detection, with limited case uses during combat (i.e. a scout engaged against a much larger naval vessel waiting for rescue). Bear in mind, as long as it has enough capacitors, it can survive any attack - purely defensively.
From a roleplay aspect, is quite likely that a lower TL aggressor would have little knowledge of the weaknesses of a black globe.