If you really think an education only takes you so far, why are you thinking of delaying your b-school plans just so you can "upgrade" to the potential for getting into H/S/W next year?
It sounds like you're making an assumption that it's not worth it to go at all unless it's H/S/W. As if having that venerable name on your resume will somehow magically transform you and open all kinds of endless doors to some secret magical kingdom. That investors will all of a sudden open their doors to simply because of your school name. That 5-10 years down the line, you will be trolling the alumni database for investors (think about it -- your primary contacts and networks will be the people you've been dealing with within the last 2-3 years -- so by the time you're a few years out of school, your b-school network will be at the periphery and will become less and less important the older you get). And put it this way, when you're 5-10 years out, it's kind of pathetic to be trolling your alumni to raise a fund (i.e. "we went to school together, so you'll meet with me right?" or even worse "yeah, we happened to go to the same school, you graduated 5 years before I did, I got a new fund I want to raise. What's the secret handshake to get a meeting?").
You're also working on the assumption that so many of the alums for H/S/W are in hugely powerful positions or are insanely rich and connected - more connected than the plebs from Darden or UNC. The truth is, most MBA graduates including those from H/S/W end up living quiet middle class lives by choice - after a few years, a good number (more than you'd expect) make career decisions (and compromises) for the sake of their family and personal lives. They don't make millions of dollars. They don't live in Beverly Hills. Most aren't CEOs or powerful titans of industry, jet setting and hob nobbing with other rich and powerful people. If anything, the "successful" ones tend to be running small businesses on their own and living a quiet life.
You also realize that as hard as it is to get into a top b-school, MBAs from top schools are pretty much a dime a dozen right (including those from H/S/W)? There really isn't anything special about a prestigious education once you're no longer a kid (read: in your 30s and beyond) and that adults will judge other adults on their entire body of work, not on where you went to school.
It's easy to see how important the name of your MBA may be for you since it's the decision that is front and center for you right now -- it's immediate and a decision you need to make right now in your life. But that immediacy may exaggerate how important the choice really is.
It's sort of like back in college and how you may have felt taking that one extra econ course would have huge consequences for your career later on. Or how getting a C- in some class will have grave consequences when it comes to your jobs years from now. Or thinking that the choice between taking the no-name company summer internship vs. Microsoft internship will dictate the rest of your adult career. You may have been proud of your alma mater, maybe even have great memories of your MSFT internship, but does it really have an immediate impact on your life or career today?
With time, you will realize how silly these preoccupations with "school brand" is on your life and career, and thinking that people actually care more than they really do.
It's easy to think that what we're dealing with currently is of biblical proportions, like the fate of the universe hangs in the balance.
If your ego can handle it, go to Darden and make the most of your time, and get on with life, rather than circling about in the hopes that branding is worth waiting yet another year of your life. Would it be great to have the opportunity to go to H/S/W? Sure. But life is short. Get on with it.