Hey there! Welcome to the forum. Quick question - do you plan on staying with one artist or collecting pieces from a bunch of people?
Both traditional and Japanese have a ton of common imagery (re: daggers, panthers, roses, tigers, shishsi, peonies, demons). I suggest finding a few artists from each style then start looking at what they are doing. Look at the people that THEY are following. Go to tattoo conventions. If you see pieces that resonate with you, ask who did the piece.
You'll need to decide for yourself if you like negative space between the different pieces. The cool thing with Japanese style is that fingerwaves, clouds and rocks always are the perfect fillers.
Where do you live?