You were probably just unlucky there. I got pretty bad results from High-Threat fleets with Radiants in them, and I got good results from medium 'invisible' hyperspace fleets. But YMMV.
A good Redacted smashing fleet IMO has at least 2 Apogees to shield tank, a couple of Afflictors/Tempests/Omens to distract and soak up attention, a couple of Beam Sunders to wreak havoc, maybe some bigger phase ships, and then a flagship you're comfortable with. Could be a Harbinger, a Doom, a Conquest... you only need to take care of the Radiants first so they don't take care of you.
You can also farm these fleets with a pair of Paragons, but that's getting boring.