Buffet they may be but a cheap one that will leave you sick and wishing you hadn't touched that damn fish. Yeah, I lost my metaphor somewhere.
Only problem I see is that, from the sounds of it, Skavis wouldn't care for heard feeding like Malvora or Raith would. Despair seems like it would be much more intimate in a 1 on 1 sense. I mean, sure, there's always group suicides but those are rarely motivated by just despair and organizing one would seem to be more trouble than it's worth. I mean, if I were a Skavis I would probably just single someone out, be it an aging, well-to-do house wife who's kids don't need her anymore and who's husband is probably having an affair with his "Younger than me" secretary. Maybe one of the sods from my local comic book store. 20-30 and some older than that yet still living off their parents without decent jobs or girlfriends (or boyfriends for that matter. It is, after all, the 21st century) or anything too look forward to in life, other than their next superhero comic escape. Perhaps one of them would like to try flying. They have nothing to live for if it doesn't work but their only real chance for escape would be if it did. The despair right before they hit the ground would HAVE to be dizzyingly sweet.
Then again, perhaps I'm thinking too small. The older Skavis would probably take MUCH more pleasure out of destroying something beautiful. Finding something close to true happiness but not quite there yet. Someone very close to it and then destroying them. Breaking them apart slowly. Something like the Book of Job. Taking everything away from them, maybe even inciting despair in just the right ways to cause them to tear apart their own lives so that in the end, before I have them finish it, they can know that they had everything in the world before them and they destroyed it all. They have no one to blame but themselves. And then I take the last of them.
At least that's how I imagine a Skavis would like it. Much more personal. Hell, even the other houses seem to prefer 1 on 1 feeding than herd feeding. They still do the herd feeding but usually only as a means to another end.