Yoichi is up past Sapporo, just the other side of Otaru, and since there's nothing faster than a local express, would probably take the better half of a day to get there, which has kept me from making it yet, but next best is Miyagikyou, both being Nikka distilleries.
My first Taketsuru was the 17 and I didn't care for the 12 at first sip, although I've now grown to like it for the price. Really the Taketsuru 12 and Bowmore 12 may be cousins of a sort.
Just had a sip of Hakushu 10 and I'd say that while the smokiness is detectable, it's not an Islay by any reach of the imagination, but something different all together and I wish they had not made the decision to discontinue it in favor of the 12, which I thought too smooth.
Too bad you're not in Tokyo or Yamanashi so you could try it without having to buy a full bottle and all I can say is that as an Islay fan, and also Yamazaki 12 fan, our tastes intersect at some points and depart on others. I like Hakushu 10, and the first time I tried it thought it nice and smoky, but I think I might have to choose the Yoichi 10 (not 12 or 15 for me) over the Hakushu... maybe.
If you can get to Yamanashi or Miyagi then a distillery tour will definitely be in order.