I agree - the TDS fantasy springs will give the Japanese audience what they want. Cute fantasy environments to absorb.Star Wars is still popular in Japan, even if not on the same scale as the U.S. or parts of Europe. Outside of Harry Potter, Star Wars is the highest grossing live-action Hollywood franchise in Japan.
With regards to TDS attendance, it's a result of not having as many attractions as TDL and also being less family-friendly (most of the major attractions are thrill rides with height restrictions). Although to be fair, TDS currently attracts more guests per year than TDL did from 2002-2011. With the opening of Fantasy Springs, TDS could finally catch up to TDL in the present (or be reasonably close at least).