For me there is so few japanese actors whom i can fave. Bc mostly nowday japanese entertaiment world goes with looks before acting skills, sadly they have excuse bc young ppl tend to confuse charm and sexapiel with acting skill.
Japanese actors whom i fave:
Kimura Takuya - He has talant for acting. Face what can express every shade of emotion, good and natural body language, he has acting style of his own and it is unique. Register of characters what he has done is from weak and whip to scary and powerful, from honest and innocent to scheming liar, from hero to villian and between. Add here his seiyuu works - what shows that he can act only with his voice and build with it belivable character, then add here his singing career, modeling. And despite of his age he looks good (to mine standart - gorgeus) and fresh, it is hard to belive what is age is...I think you get picture why i fave him.
http://mydramalist.com/actor/237/kimura-takuya
Sorimachi Takashi - nearly all same points what i wrote about Kimuras acting. Sadly his older works are hard to find but all what i have seen ( Virgin Road, GTO, Cheap Love) are superb and worth every second your time. His acting has one weird effect to me: in his dramas when his character first appeares, i notice "he looks hot" but when story goes on i kinda forget his looks and is more drawn personality of his character.
Despite searching i havent find, from younger actors generation, anyone who can stand in mine fave list with them... but i still hope find him one day.