@oedipus_tex,
I think to tackle the perceived problem here is:
Gather buff powers need to be looked at if they are consistent.
Ally only powers do they make sense with the current state of the game? If made to Gather buff style would those numbers need adjustment?
Damage boosting damage resistance granting powers needs to be fixed. This is a problem not unique to Fade.
Does having this defensive value or if other ally only powers now affect caster if those were to change would that offer too much imbalance to ATs with access to support sets? Again looking at this from the lense that Armor sets can cap their defenses easily.
Also take into account it isn't just the caster that benefits any team mate in range benefits. Most with Armor sets won't care as they are covered. So my question is, what benefit is there to reduce the defense of already less defensive teammates? If it is because other support sets are lacking that same omph then a revisit to support sets as whole might make boosted defense powers seem less like outliers.
There are other factors in play here that are being covered in other topics in regards to perceived challenge mobs offer groups and how damage has escalated in the late game. Good suggestions and observations here folks, keep them coming and some of this is going to just be opinion, what one finds easy may not be for another.