By "fair price", I mean a similar cost per megabyte transferred to what I could reasonably expect to pay for home or business internet service in that area. They can meter it and add it to my bill. So I can go nuts on bittorrent, but at a fair price. If I don't go nuts on bittorrent, I'd expect that the total should be very cheap for a typical hotel visit, especially compared to the rest of the bill.
By "good network service" I mean comparable in bandwidth and latency to residential or business service offered by ISPs in the area (e.g. cable or DSL), with good wifi coverage, and no port blocking or any other kind of filtering or traffic shaping beyond what's necessary to fight spam and provide good service to all the guests using the network.
Also, please don't restrict the number of devices. I've had hotels insist on one device to a room, or demand unreasonable feeds for extra devices. If each person has a phone, a tablet and a laptop, that's pretty inconvenient. Please bill for total bytes transferred instead.