F/1.4 & f/2
The difference in light gathering ability is equal to one f-stop (f/1.4 and f/2).
The apparent focal lengths are 35 x 1.6 = 56mm and 50 x 1.6 = 80mm.
If you use the 50mm lens it will be like using a 80mm lens on your old film camera.
If you use the 35mm lens it will be like using a 56mm lens on your old film camera.
If you want something that will perform like your old set-up, the 35mm lens will be the nearest.
However you will lose one f-stop in brightness.
But your film camera needed special fast film to work in very low light and with the digital camera you only have to change the ISO setting. I doubt that you will miss that one f-stop.
If your concern about the 50mm lens is portraits, not to worry, as 80mm is also a good portrait focal length.
However 80mm is not a good choice for wide-angle shots.
You have to decide which is best for you.
Someone else can not make that decision for you.