To be honest, I somewhat disagree with an open attack on the Minbari Protectorate since I think the Minbari are wayyyy too tough for the Orieni plus the ISA would support their allies but its up to the people how they want to run it
Remember that the Minbari Protectorate isn't the Federation proper; the militia are nowhere near as well armed as the warrior caste (see signature link!)
I wouldn't think the Orieni would be dumb enough to take on their master's favoured sons in open battle (but I guess you never know), but striking during the Drakh war means that the ISA, EA and Warrior Caste are otherwise occupied. Not to mention that many of the worlds of the protectorate are former Vorlon servants from the last Shadow War, so would be attractive to the Orieni as 'those led astray by the apostate Minbari' that they can go and 'redeem'.
They could, for that matter, do it in proper ori fashion; go in as missionaries, seek converts (a lot easier than normal for telepaths :wink: ), and 'defend themselves' in a violent fashion if the planet's government tries to eject them once they become entrenched. Not covert like the Drakh, but in its own way just as insidious.
The minbari would no doubt get annoyed, and potentially even concerned, by a new religion sweeping through minor races near their space which paints them as Lucifer incarnate but they aren't being directly attacked...nor are the Orieni race 'responsible' for the acts of individual preachers (honest, guv)
Technology-wise, they did take on the Centauri but that was the early republic fleet; the
Primus-class battlecruiser, if I remember correctly, was the final, high-tech, nail-in-the-coffin Centauri development. Whilst the Orieni Empire might well have developed itself in the intervening time, given the theocratic control and insular nature, they probably wouldn't have developed as much.
As noted, though, they would probably have gone into vorlon space after Corianna, looking for sacred relics, etc. This would have probably cost a lot of ships but it would be better than leaving relics around for the Minbari or Humans to loot (sadly they still stole at least one lightning cannon and quantum-space drive). In the case of the crusade's command ships this might translate to limited vorlon technology, but would be more likely to be 'bolt-ons' like a shadow omega than properly integrated like a white star. In fact, I can imagine that they might well get obessed with vorlon relics and the 'unfinished plans' of their gods - to the point that one starts seeing a certain resemblance to the
Halo-verse Covenant.
If they gain ISA membership, though, the secularists might rapidly learn to produce true vorlon-tech ships rather than crude hybrids - but then it would mostly be the priests who would have the vorlon artifacts they'd need. Would they share with anyone who abandoned the faith?
The Orieni Fleet as seen was:
Flocks of small ships
Obedient-class Patrol Frigate
Steadfast-class Escort Corvette
Benevolent-class Heavy Scout
A few big ships
Prophet-class Command Ship
Paragon-class Strike Force Command Ship
And
Hunter-Killers (remote-guided suicide fighters).
The trick will be (a) making the fleet feel right so that you have a heavy and light bias without midweight ships without the priority points system falling over. I might suggest including raid-priority "two-fors" or "three-fors" and (b) stopping it feeling like Gaim or Dilgar.
