I focus on the harp, and play the other instruments as I can find the time. I have been playing some things much longer than harp so with them it is more about keeping up my ability and doesn’t require a lot of time to actually learn new things.
Someone commented about doubling with very different instruments and how rare it is. True. I was always very impressed by Derek Bell. He held positions as principal Oboe with several orchestras as well has principle harp for the BBC Northern Ireland Orchestra.
Doubling is one thing, but to win positions as principle on two different instruments is very impressive. Not to mention that he didn’t even touch the harp till he was almost 30.
I will say, playing other instruments has definitely made me a better harpist. I often think of what can be done on other instruments and it inspires me to try new things on the harp, and to just look at music in general from different perspectives.