I think one thing his early season eye test has shown, is that when he's been struggling he's been really in between. No real conviction on swinging early at good pitches, he panics once he gets to 2 strikes and does weird half swings because striking out is dishonourable in Japanese culture or whatever.
I think if he can't over having his best "A" swing at all times, or isn't good enough to stay alive on 2 strike counts, then he needs to be swinging earlier looking to do damage. Part of this I think hopefully can come during the adjustment period, once he gets more comfortable with how the league approaches him. He's a very powerful hitter who can do serious damage to all parts of the field, and can connect on velocity. The early numbers show he doesn't chase a lot, and I think he can get even better here once he's less in between after getting more exposure to MLB pitching.
Take your walks, swing hard all the time, and try to do your damage early if 2 strike counts continue to be a problem. I think this will indicate if he needs to be swinging more or less often.