The most important factor for the wood floor chosen is structural stability.
According to the USDA Forest Service, this list shows most dimensionally stable to least:
Engineered is the most structurally stable compared to natural hardwood, so it will work the best with floor heating.
If you do want to go with Hardwood, quartersawn or riftsawn narrow planks are the most structurally stable and would work best for this application.
Overall the most important factor for the room is relative humidity. Keeping a consistent humidity and temperature in the home will help wood floors last for many years to come.