You can separate the inlet valves from the drain, code doesn't require them being together. Code requires the drain p-trap to be above the floor and the fill pipe to be at least 18" long. It's recommended to have the fill pipe at washer height but it's not required by code, the fill pipe is used to let suds accumulate so they don't spill on the floor.

http://www.plumbing-geek.com/washing-machine-drain.html

Thank you Plumbing Geek, that is very helpful! I looked at your website and found lots of good info.

I found a wonderful dual valve that has a short stem with a ball knob that you turn both hot and cold water lines on with at the same time. Mine is solid brass and I like the look and feel of it. It is easy enough for my wife to switch. I think stainless can be had for more money. A plumber installed it . Our stand pipe is behind a sheet rock wall, except for a very short pipe that Y's off at the top and protrudes out of the wall. We stick the drain hose into it. No problems with backup or smells.

I just checked and Amazon.com has them for as low as $14.95, The knob is not a ball and neither is ours.

I hid mine in a false back in the cabinet. It is located as needed to prevent syphoning I believe. It is located within the cabinets of the laundry surround.