Must visit BhagsuNag Falls at Mcleodganj with atleast an hour at the falls. On the other hand Dal lake was a big flop show. St. John's Church, Dalai Lama's temple are worth visiting. River rafting at Kullu is good but if you have already been to Ganga white water rafting at Hrishikesh then this would be a little less thrilling for you. Rohtang Pass and Hadimba Temple is a must go in Manali. If possible hire a bike for a trip to Rohtang. This would multiply your fun. Also get going on the journey as early as possible. Enjoy the trip!!