You're opening up a can of worms when you ask a group this size "what tire should I buy?". You're going to get a lot of suggestions. The first thing that comes to my mind are Continental Travel Contacts.
Those Specialized Nimbus are not "premium" tires, like Continental or Schwalbe. They're only 30TPI and even though they're narrower than the Travel Contacts, they're actually heavier.
Like I said, you'll get a lot of different suggestions, but it's worth buying good tires. Continental, Schwalbe, and Maxxis all make great tires and are worth the extra money over the bike store service brands like Specialized or Bontrager. Tires are not the place to economize when it comes to your bike.