Tamshing Lhakhang is just one of the landmarks located 0.5 mi (0.9 km) from central Bumthang, so you might want to stop by for a few pics during your trip.
If museums are on your list of things to see in Trongsa, then you might want to head to Tower of Trongsa Museum. If you want to experience more of the culture Trongsa has to offer, head to Trongsa Dzong.