For a few months, I've been riding Vittoria Voyager Hyper tires, formerly called Rando Hyper. They are not so heavy for their size. Tread is pretty minimal. Flexibility and perceived speed is quite good. They feel lighter than they are, and they aren't all that heavy, either. They have some kind of flat protection, which was not a selling point for me, but I'm glad to have the benefit, as it doesn't seem to make the ride worse, not that I've done a side-by-side comparison. They also have a reflective sidewall on each side, which really is a plus. I highly recommend these, except that they don't look good for snow or mud. I think you really need a different tire for the sloppy stuff in winter.

I strongly prefer tires from one of the big tire makers, as they are on the cutting edge of R&D. Vittoria is one of those companies. Schwalbe is, too, but they charge a premium for their tires, and it's not worth it to me. Plus a lot of Schwalbe tires get bad reviews for the way they ride.