Fans of lakes are spoilt in Ladakh. Tso Moriri and Pangong Tso have amazing colours. Depending on the time of day, they can be very changeable: blue, green, turquoise. To best appreciate them, I recommend that you stay nearby. In any case it's not conceivable to do the return trip from Leh in one day.
The lake is located in the Indian part of the Tibetan Changtang, a very high plain. On the way you can see mountainous landscapes which are very different to those in the north of Leh (yes, it's possible, Ladakh is hard to predict!). The most interesting thing is to meet the nomads who set up camp beside the lake in the summer.
However, during a trip to India, it's completely pointless to go on a trip to Tso Moriri if you've seen Pangong Tso. You should choose one or the other. Personally I saw both and I preferred Pangong Tso because the journey there seemed more interesting.