The only flaw of the anthology is... well, the concept itself, and the fact that every writer obviously felt compelled to shoehorn a line or two that would emphasize the story's connection to the sin it is supposed to represent - even when it's a very loose and far-fetched connection (Ravenant, a great story, which however has nothing to do with Gluttony, despite the insertion of the word hunger several times in the story; including the reference to Walsh's "hunger" for profit, which is really greed).
Hmm, well, gluttony doesn't really mean hunger, it means over-consumption to a wasteful degree. So it's not just about wanting to consume, it's about consuming too much, particularly if it's at the expense of others (e.g. eating so much of a limited food supply that others are left to starve).
So one could say that "Revenant" is about gluttony, because the Borg's "consumption" of other species is very wasteful and very much at the expense of others. And the mission to obtain Borg technology comes at the expense of the people sent to that ship, I guess. Okay, that's more of a reach, but I can still see how gluttony would apply in general to the Borg. If you devour everything in your path and leave nothing behind, that's gluttony in spades.
I also enjoyed seeing everything else from Brunt's perspective, which are more typically Ferengi than Quark's - for instance, his appreciation of Ferengi female beauty and disgust at alien, including Human looks. (Quark and Rom can't be typical in their appreciation of clothed female beauty of many tall alien species.)
It is pretty standard throughout canonical Trek to see Ferengi demonstrating attraction to other humanoid females, from DaiMon Tog trying to woo Lwaxana Troi in "Menage a Troi" to Lenor and Qol trying to buy Kamala in "The Perfect Mate" to Ulis's crew in "Acquisition" planning to abduct T'Pol and Hoshi as slaves.
Wrath: Klingons - "The Unhappy Ones"
I haven't read any of the Klingon-related fiction related to the conflict between the smooth-heads and the ridge-heads, so this was a new theme to me.
It's never really been addressed in this much detail before. The old novel Faces of Fire
and Vonda McIntyre's ST III novelization both talk about conflicts between Klingon factions or racial groups, but don't explicitly identify them as smoothies and ridgies (though I've always assumed that was the intended implication). In the Name of Honor
addressed it to some extent, and Excelsior: Forged in Fire
touched on it, but I'd say this is the fullest development of the issue in Trek Lit, certainly the fullest one since the origin of the smooth-headed Klingons was canonically established.