Shirdi is a very nice, calm and religious place. The best thing about Shirdi is that everything that is absolutely necessary for traveling is available here like hotels, dharmashalas, travel cars, restaurants, medicine shops. One day is enough for visiting the temple of Shirdi Sai.There is a long queue for main darshan but one can go and sit a hall for mukh darshan and see Shirdi Sai from a little distance.
In the second day, can cover Aurangabaad which has many attractive places like Bibi-Ka-muqbara, Ellora caves, one Jyotirling near Ellora, Sleeping Hanuman temple and many more temples to be explored.One can easily cover all these places and return to shirdi in 1 day(Leave Shidhi at about 9 am and u can cover all these places return back to Shirdi within 8 pm easily).
One day needs to be reserved for visiting Nashik which has many temples, Ganga ghats, caves, etc. Trimbakeshwar, jyotirling of Mahadev can be also covered in the same day.Many temples can be skipped if one has less time but i think that everything can be covered easily in a day(same departure & arrival time as that of day 2).
In day 2 and day 3 also one go to the Shirdi temple in the night after arrival at around 9 pm.
Overall it was quite an enjoyable and fruitful journey.The people here are very cooperative and helpful.3 days are enough for covering Shirdi and its nearby places like Aurangabaad,Nashik and Trimbakeshwar.Do visit all the places mentioned which make your journey enjoyable,exciting,complete.