I got 60 farm, but I'm still enjoying it, so I might as well keep on going.
I've been doing maple trees and pineapple trees in Catherby & Taverley. I can use my Amulet of Nature to tell me when Maple tree is ready, and check on my pineapple as I pass. Also, I have learnt how to use the Catherby Cliff Shortcut, and it is very useful and saves a lot of time.
I reckon I will keep going until 65 or 70, but there is nothing I really want to plant, so it doesn't matter. Long term, I want to get 85 so that I can use Spirit Trees, since I can put them in strategic places to help me get around.
On the other hand, 85 is fucking hard...