We try to mix it up. Here's where we went last winter: https://blog.ycombinator.com/winter-2016-college-tour/. And last fall: https://blog.ycombinator.com/yc-office-hours-in-11-countries...
And I have to ask: If the Ivies/MIT/Stanford aren't the only schools that matter, why call them out in a post that's distinct from the winter tour post?
I can't imagine the amount of crying from the community if the hosts of the site would take special privilege to pin their posts at the top. (I'd be fine with it, as it's their house, but I think they actually are better served to only take a small privilege with the jobs and show posts and otherwise leave the site to the users to vote/curate.)