My FS-5G doesn’t sound boomy to my ears. It’s louder than most sopranos, and it has a full sound, but I’d not describe it as boomy. I had imported it from Japan in 2016, and it is strung with Living Water strings. Experimenting with strings is a good idea. I didn’t really care for the nylons it came with (I felt they made the uke sound a little dull), but that’s always individual preference.