Yes indeed. Green Bus is based in Chiang Mai and operates routes in the North of Thailand, mainly in Lanna (not Isaan). The company has smart, modern, air-conditioned single deck coaches which serve many towns and cities from the main bus station (near the Super Highway). There are reasonably frequent services throughout the day to Chiang Rai, Maesai, Maesot, Phayao, Nan, Golden Triangle, Lamphun, Lampang, Chiang Saen and Chiang Khong (both the latter on the Mekong). Whatever destination you choose there will be some scenic mountain views. I was a Tourist Police Volunteer based in Chiang Rai and I often saw Green Bus at various bus stations during patrols.
May I suggest a trip to Phayao from Chiang Mai which traverses 2 main mountain ranges (Doi Saket to Mae Khachan then Wang Nua to Phayao). This can be achieved as a day return tour, if you start early in Chiang Mai. However one night in Phayao would give you plenty of time to explore the lakeside with its long promenade. Plenty of bars, restaurants and hotels. (photo of Lake Phayao from mountain road descending to Phayao)
Green Bus:
https://www.greenbusthailand.com/website/en/services/bus/bus-route