I tend to run Elite Fleet Warp Cores that transfer Weapon power to Shield power, increase Shield power cap to 130, and provide +.3.3% damage per 75 power level, can't remember more specifics about them and they might not be the most optimal.
Besides that, Elite Fleet Resilient Shield (Resistance B), which has a 5% bleedthrough, adapts to damage types, and resists Disruptor, Plasma and whatnot. Best shield around last time I checked with Norfleet.
Borg Deflector and Engine for extra power and the heal proc, though the proc may have been nerfed. Still, it's either that or Omega 2/3 for Tetryon Glider, HG 2/3 for Torp damage bonus, full MACO to skip on Plasmonic Leech, or MAYBE if you use Polaron than Jem'Hadar 2/3.
For Space weapons, I tend to use Elite Fleet stuff. The Fed shield heal proc at least seems to give a little extra edge of healing, and the KDF disruptor proc is awesome. Rear always has a Omega Cutting Beam to synch with the Borg console. Torps are either Romulan Hyper-Plasma, Wide Angle Quantum, or Dyson Gravimetric, and some Escorts of mine have a manually fired Transphasic Cluster Torp (Norfleet has some new info about the viability of full Turret loadout in an Escort's rear).
Must have consoles are Fleet Elite Tacticool consoles of chosen energy type with +Crit Chance, Plasmonic Leech, Borg Console, and Romulan Zero-Point Console.
And yes, the Borg Cats from B'Tran are an excellent idea for the Tempest, given how it can easily run Aux2Bat unlike just about every other Escort in the game. The other important thing is a Suliban Taliban reverse shield polarity booster doff, and I think I got one lying around my mailbox or roster for Fed.