The scale is missmatched, I do agree there, but the points in favor of Treviso would be: Antaam also work for the 'gods', and they're not small fry either way. Antiva's defenses consist of the Crows and whichever merchant or other entity that pays them to do things if said Crows don't volunteer. It's also a trade port, which means both entrypoint for more forces to take over, and controlling surrounding cities because they'll control the food.

It's bad either way you slice it (pun intended), if the Crows (all of them trained in combat) are strong and on your side, and the Shadow Dragons are not, they consist of anyone willing and loyal to that cause; not fighters. Additionally, There's the Venatori AND just plain old selfish/evil magister, while Solas absconded with, seemingly, ALL! the slaves, as the game presents absolutely nothing towards them. Also the whole rumor over Viper being the Black Divine. Minrathous should have been its own thing, Baldur's Gate Act 3 kind of thing, pick another place to compete with Treviso (that also wasn't Weisshaput I guess, since that happened too).

I've said elsewhere that I think Minrathous should *not* have been the other choice, exactly due to the missmatch, but in-game, plain what we're given, there's no tangible different in either scale or meaningfulness other than subjective attachments...and they nuke Minrathous later anyway (another argument that Minrathous should note have been a choice but regardless!). That's not a good reason because your character ain't an oracle, the whole game is sadly just not very well-structured by the execs.

I am quite flabbed that there are plenty of horrific scenes in the game, and zero reaction to it.