Keep in mind the Jovian research of the electromagnetic phenomena betwen Jupiter and Io. They didn't figure it out "just" because of the Lucifer or the defecting ships from the 14th Battlegroup.
This. The Oculus is so effective at beam jamming because its normal capabilities is geared toward dealing with extremely high levels of magnetism; as a military application, it's more than just software, it's a unique level of hardware AND the expertise and scientific understanding that comes along with the package.
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To the thread's main topic:
1) Pick off as many ships as possible (though they should probably Sanctus-class at least); use highly disproportionate force to do it, and be unpredictable.
Regularly have Pegasus and Aurora fighters do recon and 'vectoring' for potential shock jumps. Even if it's right outside places like a Kumari.
Lure out a frigate or Sanctus with large numbers of minor, but significant, strikes; always make it seem as if it's a small engagement and that a relatively small force commitment can save the situation. And then, on a good number of these occasions, actually let them succeed. So when you get the right opportunity and a Karuna or a few Sanctus cruisers comes in, you can feasibly vector in a shock-jump with Serkr Team (or just the Atreus herself; her capability and reputation for impossibly rapid subspace jumps would make even Calder hesitant to bring in the cavalry right away, giving the Atreus the time to escape without too much trouble).
Every time there's a minor engagement, send in a ludicrously disproportionate force to take out the UEF assets present. Given Byrne's passivity, the general friction between Byrne, Netreba, and Calder, Calder's famous aggression and the autonomy between 1st and 2nd/3rd Fleets, they'll be much less responsive to offensively committing a massive force deployment, especially after the events of Delenda Est. For ships with sprint drives, the window of opportunity to counterstrike would be quite limited to begin with.
2) In major engagements, have a wing or two of Ares fighters be dedicated to warhead intercept and point defense against UEF gunships, bombers, and (depending on the circumstances) Kents. With Maxims in the two-gun slot and Balors or Kaysers in the four-gun slot, they can pick off an impressive number of torpedoes and send a lot of Trebuchets to targets. Even if they're dodged, they've left the heavy strike craft vulnerable and averted their attacks for the duration of the missile salvo. They have very powerful reactors, strong shields and armor, and enough speed and maneuverability to effectively supplement/escort a capital ship. And, of course, at ranges within 5 km, they can use their Trebs to snipe turrets of value (like the Torpedo launchers, mass drivers, etc.). Use Herc-II's as a substitute if necessary.
3) Supernova SSM's. PLOX.
4) Split up Serkr Team when not targetting pairs of Karunas or a Narayana; each of the corvettes is paired with either a Hyperion or a Deimos and Aeolus. The threat being that, while not quite being able to one-shot Karunas (unless it's a Bellerophon and Deimos/Aeolus), they can definitely do it in two, and any attempt at a counterstrike would also face the threat of a subsequent shock-jump by the other two portions of Serkr Team. This is just an idea, no idea if it would work in practice, but still. Fun to think about.
5) Try to keep Byrne on the passive defense, and exploit/fuel the friction between Byrne and Netreba/Calder. Unless you get a golden opportunity, don't destroy the Toutatis or too many 3rd Fleet assets, in order to continue and exploit the lack of unity between the UEF fleets.
