Considered to be a Maverick in the HK Film industry, Tsui Hark did some of his best work with jet in the "Once Upon A Time in China" movies. Tsui brings stylish shots and sensibility to a movie, and that's precisely what was done with jet. In addition, Tsui has probably been the producer for lots of Jet's movies
Although he has not the critical acclaim some of the other directors, Corey Yuen Kwai has crafted many a Jet Li masterpiece. His folk adventure, Fong Sai Yuk, has often beem praised for its blend of humor, drama, and excellent choreography. Corey's films continue to reap in a good profit at the box office, meaning he will probably keep maiking flicks for a while.
Well-known for his "juvenille" sense of humor, Wong Jing crafted many a Masterpiece with Jet (depending on who you ask). There is no doubt the Wong knows a good level of action to go into a movie (too much is NEVER enough), and does so on each occassion.
Undeniably one of the last great kung-fu directors of the '70's, Yuen Woo Ping has made spectacular fighting flicks with every big chinese star, It was only a matter of time before he worked with Jet Li. Yuen's choreography is among the best in Hong Kong, (he choreographed Fist of Legend,) and will certainly continue to bring him fame and acclaim until the day cinema is abandoned.
One of the "three brothers" (along with Jackie Chan & Yuen Biao), Sammo is easily the best KUNG-FU director of the three. Seeing as fighting is his forte, it's no suprise he eventually worked with Jet. Sammo often brings his unique blend of humor and fighting to the screen, and this formula has proved to be successful many times in his hands.