You know this is one of the few episodes of DSN, I've only seen 2 or 3 times. Not one of my favourite episodes.
Yeah, it was a fairly transparent attempt to have Kai Opaka fall on her sword nobly so pave the way for Winn's rise to power.
On one hand it's a pity, because I liked the Opaka character, on the other Winn was such a delightfully wicked antagonist. Though it was nice Opaka showed up regularly in flashback.