Honestly, I think you'd be best served going exclusively Greninja. That character is legit fun and one of the few in the cast I've played where everything just feels right/you aren't running into an artificial wall every time you do something. It also helps that his "gimmicks" aren't all hit or miss. Dude can put you in the blender forever and actually hits hard when necessary (sorry Sheik).
Greninja gimmicks go up online. I saw you do that mash counter twice into forward B when I tried to punish the first counter lol
Offline though, Greninja still represents my dislike on how Smash 4 neutral is though.