My oldest son and my wife have just returned from 5 days in Marrakech (28℃ during the days, 13℃ during the nights). And they loved it. It's not a town to stay for more than 6 days or so. But it's perhaps a nice spot to go to during the winter.
There's definitely a French influence in Marrakech (and a Yves St. Laurent Museum with a beautiful garden) and they did a trip with a guide into the desert. And they spent a day a the Royal Marrakech Golf Club, which is a A+ location if you play golf.
It's not the busiest holiday period and they stayed in a small (only 6 rooms) hotel. The food was fantastic and punctuality is one of the people's virtues there.
On behalf of them: recommended.