I think I'll probably just simplify the arrangement. Was trying to be clever rather than actually working out what suits the song! Too many notes in it.

In my head, I keep hearing the sort of lovely jingly sound that Shirley Collins had on that banjo-lute thing she used to play - the instrument at the start of 'I once loved a boy, a bonny bonny boy' on whichever 1960s album that was

I have just had some enjoyable procrastination looking at guitaleles on the Thomann shop. I like the sound samples of the Yamaha GL1:
https://www.thomann.de/gb/yamaha_gl1.htm

Might be on the shopping list for when I get paid