Matusow.... you get karma.... hitting a gaurdian w/vengeance could be powerful in pretty much any fight, I would think.
Also, if any of you think the radiance has no utility, what we need to know to resolve the argument is this: is there a stacking effect of increased weapon damage for SC combined w/ weapon damage research? If you've built a Rapture in the early game, by late game your SC's (assuming they stick close to the Rapture at all times) could be getting a 69% damage increase. For example: say a bomber does 34 damage. increase this by 30% (from beam damage research):
34 X 1.3 = 44.2
Now, if our Rapture applies it's damage bonus to this post-research value, the result would be:
44.2 X 1.3 = 57.46
On the other hand, if the Rapture's bonus damage were applied only to the base weapon damage (pre-research), the total weapon damage would look more like:
(34 X 1.3) + (34 X .3) = 54.4
This may not seem like a huge difference, but when you consider that advent squadrons consist of 7-9+ members (halcyon or hangar bays), a mere 5.5% difference could shift the outcome of a battle significantly. Also, assuming it were practical to pump out two halcyon carriers (at the same time a rapture and mothership), and get both carriers to level 6 as well as the Rapture's meditation ability to level 3 (+30% damage), it could be a game winner (if your opponent doesn't spam fighters/flak appropriately). Here's why: each level 6 halycon carrier has 4 squadrons, each with +3 members per squadron. As a side note, the best way to exploit this ability is to make them all bombers, i think, since you go from 7 to 10 bomber members as opposed to 9 - 12 fighters; using fighters gives a smaller percent increase of damage. Anyway, at level six the halcyons can release a swarm of 30 SC each, lasting for 75 seconds. That's an extra six members per squadron. That's eight bomber squadrons w/ 17.5 members each, or in other words, 20 standard bomber squadrons. But wait.... we have a rapture ability and research multiplying their base damage (pre-research) by either a factor of 1.6 or 1.69:
54.4 / 34 = 1.6
57.46 / 34 = 1.69
That's if you've done all your beam damage research. Do you see why this could become an issue to resolve? Add to that maybe another 20 - 30 other squadrons from drone hosts (if this halcyon/rapture combo was part of your strategy, you would almost certainly capitalize by building several drone hosts), and that extra 5.5% could become an issue in an argument where the Rapture's role is being scrutinized.
However, the only time that I could see this Mothership/Rapture and double Halcyon strategy being practical is if you have a reasonable resource pull (4-5 planets, not including asteroids), and have a single choke point as your only exposed node, with of course a starbase and upgraded defenses. If you couldn't see an immediate advantage in pushing out (in a team game, multiple opponents who might coordinate attacks on your overly exposed push) at the moment, you might dig in and decide to pump out up to 4-5 capital ships in order to capitalize on the XP stream from multiple opponents attacking you. I could see that being an excellent time to try this combo, as the Rapture meditation ability would be invaluable for boosting damage from defense-hosted drones (starbase and hangars), and later adding multiple Halcyons would help further capitalize on the SC strategy if you saw that your opponents weren't respecting (not enough flak/fighters) just how disgusting your SC cloud would be after an hour of feeding you XP. If you had the luxury of hiding say something like 10 - 15 hosts on an inner planet (if you had relatively competent teammates applying just enough pressure), waiting for the right moment to reveal them in a massive SC blitzkrieg, it might surprise your opponents.
On top of that, as previously mentioned, if you have a Radiance (instead of a second halcyon) pulling aggro from up to 24 targets, the Rapture can simultaneously buff damage on SC (passive ability, no antimatter required! you have to kill that motherfucker to end it!) and deal up to 200% damage to all 24 targets that are currently forced to attack the Radiance. This makes the Radiance become sort of a bomb rather than a cap ship, but the payoff is 24+ ships that will disappear before the Radiance heads for the coffers. Then Resurrect his crew (awesome mothership ability, almost as badass as the TEC Akkan's Armistice) into another Radiance, and he's back to kill more (fuckin Cylons).