Of the same kinds, class, or nature

I was going to suggest buying books cheaper online, but it sounds like B&N is the best move for you now. If you're thinking about going with single issues, but it's not essential for you to get them the day they come out, try Discount Comic Book Service, a web-service that lets you order the books at a substantial discount and have them delivered. You have to pre-order and the process seems a little tedious (I've never done it), but it seems to be the most cost-effective method.

Some people download, which I don't fully endorse, but I'm sure you could find out how without much effort, and could still buy the shiny collected versions later with your gift cards.

As for reccing more collections -- have you tried your local library? Maybe see what they have and figure out what you like? Do you have any idea what other sorts of books you might be looking for? I always recommend (and probably have already recced to you) X-Men First Class and Wolverine First Class. But those aren't in the current Marvel Universe. Depending on what you like about Utopia, you might want to try New Avengers or Dark Avengers or Warren Ellis's run on Thunderbolts, or Iron Man, or certain story arcs of Spider-Man. If you want to get a book coming out now, maybe go a couple issues back and start X-Men Legacy. And have you read 'Astonishing X-Men' already? I think you have, but if not it's basically a prequel to S.W.O.R.D.