You should definitely buy a pair of Vass but maybe not three unless you feel very comfortable with different lasts. I'll give you my 2 cents: I don't really like round lasts (I mean really old school round not like EG 202). However, this is something I've developed with time. Although Vass has expanded their lines, I feel that they mainly make old school Austro-Hungarian shoes which you might like, but I doubt it since you moved to slim jeans. My point is that you may actually find only one pair that is sleek and casual as you're looking for. For casual shoes, I really like full brogue oxford (think C&J Clifford). In the US, some people would say that oxfords are only for suits, but that again is old school thinking. If you go to Paris, you'll see people in shirts with French cuffs and no jacket. It's more about showing your style. In the US, if you'd do that, people would think you're trying to show off. This should also be influenced by your environment. It's probably true that Vass prices will increase in the future, like Carmina or Scafora. So get them but in moderation.