Startropics was a big hit in the US. It’s engine was a turn-based version of the Zelda engine. Note that original Legend of Zelda wasn’t on the NES.
Furthermore, I really felt that this was one of multiple JRPG franchises Nintendo had with US charm. The others being:
Mario & Luigi
The games have a quirky sense of humor and somewhat inspired by realism such as Earthbound’s urbanism, Pokemon’s nature background being a predecessor to that of Silver Spoon.