I gather the fleet of this secret cabal has every right to resemble that of S31 in DSC: the bulk of it is special purpose vessels, very special, optimized for the weird job the cabal has undertaken.
S31 had fancy low-signature spyships for insertion and extraction and drone action and whatnot. Zhat Vash might have built up for the inevitable invasion of the AI homeworld instead. Although I don't quite see what they would hope to win by invading in winged spacecraft - surely they expect to be outgunned by this evil AI they so fear and loathe, and surely their best bet would be to deliver a WMD or a million in a maximally surprising way? Flying all the way down to the surface would appear the antithesis of that. Especially as half the force appears to consist of the glorified shuttlebuses transporting personnel to and from the Artifact.
I do like the idea of Oh only commanding midget ships, even if plenty of them. But it makes me wonder what happened to all the behemoths, and why Oh isn't concerned some of those will show up and ruin her day.
All that said, the winged transports are excellent for their job, dramatically, aesthetically and by in-universe logic. The two new designs from the most recent ep, perhaps not so much. And the scout just continues the long Trek tradition of building a minimal shape around a cockpit that exists as a prop, and is fine as such, plus good continuity...
Timo Saloniemi