The bowed psaltery is what I take along when I have a space problem. I don’t play it otherwise, but then it’s strictly a melody instrument. (Some people add chords by laying the psaltery flat and playing with two bows.) It’s not an early instrument, BTW. It shares only the name with the mediaeval instrument. It was invented by a German music teacher in the twentieth century and it has a zithery sound.
I can’t afford more than one harp or I would try an ancient Irish/Scottish style harp. It wouldn’t do for my only harp.