Bit of a noob on the league maself
Yokohama F Marino's
Marcus Tulio Tanaka ( got player of the year award last year)
Shunsuke Nakamura for Celtic
Shunsuke Nakamura again legend
Improving the Japanese game i would say stop signing old Brazilian has beens and concentrate more on developing youngsters so there is more high profile Japanese players around the world in the future so the J League has a reputation of breeding good players then work there way to being a better league.