Sliding dropouts are the way to go. I have two bikes with that system, an All City Super Professional, and a Kona Unit. The Kona's version is more secure, but the All City's offers more precise adjustment.
One advantage of either is that the disc brake caliper moves with the axle, so you don't have to adjust (or even touch) the brakes when tensioning the chain. The other advantage is that the wheel drops right out when you need to remove it, and when you re-install, no further tension adjustment is needed.
