As Rajasthan is a very hot place so visiting in summer there might make to exhausted by the heat. Where as in visiting in winter may also not be the very perfect experience due to the cold and all that stuff , so it would be best to visit either it the starting of winters or the ending of winters so that you can have a proper experience of the place with traditional cold drinks and hot bonfire. Also the temperature is favorable to visit all the places you are wishing to.