@Katie
I host long-term guests these days and, at the moment, WiFi and desk/workspace is what seems to be front of mind.
The next most important thing is the kitchen. Guests use this frequently, but there's not much 'real' cooking going on and some people say they love to bake but I've never had anyone actually get on and do it! The microwave gets more use than the stove/ovens. The only guests - short or long-term - that do a lot of full on cooking are Asian.
Short-term guests would also often tell me they were attracted by the roll top bath, but hardly anyone used it. Those that did were almost always American. I would have thought in the Summer months that the garden and roof terrace would be big draws, but most guests don't use those that much either. It's funny what people think they want versus what they actually want/need.
I don't think they count as amenities, but the location close to the centre/with good transport connections is a big draw, as are my cats!