In my mind, I thought about what I would view the final product on.
8.5" by 11" (AR = 1.29) photo paper, 13" by 19" (AR = 1.46) photo paper, 8" by 10" (AR = 1.25) photo paper, My 15" UHD (4K) (16 by 9) (AR = 1.77) laptop, Our big screen UHD (4K) (16 by 9) TV (AR = 1.77), my desktop UHD (4K) computer monitor (16 by 9) (AR = 1.77). Since my most often used display devices are (16 by 9) (AR = 1.77) I plan everything toward the aspect ratio of AR = 1.77. My wife and I have this discussion every several months when she looks at some old photos at 4 by 3 (AR = 1.33) Then we bought two Samsung Android tablets 8" and 9.7" (4 by 3) (AR= 1.33). Gad what nightmare when you have taken and stored photos for about 70 years! Yes I was processing Ansco color film in my closet under the stairs when I was 12 years old - ha ha.
I hope this helps.
Joe
KC7GHT