If you come early in the morning, you may have the chance to see the pickers working in the plantation and obviously there will be fewer visitors. Choui Fong attracts a lot of people who come for some pictures and selfies. As for me, coming from Chiang Rai especially for the plantation does not necessarily worth it ( Singha Park is much closer to the city and also has a nice tea plantation) but adding Choui Fong as a stopover on the road to Doi Tung or Mae Sai can be a good idea.
To go visit Choui Fong Tea Plantation, you can also book one of the tours above.