I spent 4 days in Morocco just before Christmas and loved the place. Although the majority of the time was spent in Marrakesh (not ideal) we spent a night in the Atlas foothills where the scenery was absolutely amazing. Unfortunately one of my friends has hurt his knee so we couldn't get up into the mountains proper.
We used a travel guide (booked in the UK) when in the country to arrange all of the transport, i would definitely recommend you do the same to avoid suffering from any potential scams while in the country and take reduce stress.
We had excellent weather and could wear T-shirts during the day and even a jumper was enough in the evening (although we didn't got that high).
A few obvious (but still important) suggestions, stock up with bottled water for your walks and be careful with your valuables, cameras etc.
We found the combination of friendly people and scenery great though, i hope you do go and have a wonderful time.
Matthew