The white temple is really very beautiful, I've been there several times, I can highly recommend it. But choose the time well, unfortunately it is often very crowded.

And if you are already in Chiang Mai, then also visit the blue temple Wat Rong Suea Ten, it is from a disciple of the white temple builder (OLC: 7MFXWRFR+8P).

You should also visit the big white Buddha at Wat Huai Pla Kang, which even has an elevator to the top (OLC: 7MFXWRX4+HH).