If you have time en route to Tso Moriri, it's well worth having a quick look at the charming villages of the Rong Valley between Upshi and Mahe Bridge.
The picturesque village of Likche is invisible from the road but has a small gompa and traditional houses huddled against a cliff. Himya, 10km further, is another charming village that has a couple of simple restaurants and is worth a stroll.
Most people only stop for lunch at Chumathang, the largest village in Rong, but it's worth detouring to the monastery above town for its fine overviews.
There are traditional homestays (per person including half board ₹800) in the villages of Likche, Himya, Tugla (above Likche), Kesar, Himya and Khatpu (above Himya).