I think that's a little harsh, the rock/memorial garden is minimalist but very effective, and should be nice with the water feature. I also really like the fencing used around the ride, it's high but doesn't obstruct the view of the coaster - quite an underrated design feat really when you consider how many parks completely block otherwise brilliant views with fencing.
I had hoped for more greenery in line with the "Japanese garden" theme, particularly around the second half of the ride, but the stones they have look smart enough.
My big issue is the station. You've got a stylish, perfectly streamlined coaster and modern trains with some nice minimalist theming, but then a massive shoebox covered in cladding which completely ruins the feel and flow of the ride. I'm not sure what the cladding is for, had hoped they would grow some foliage on the sides but it doesn't appear to be the case, therefore it looks a bit out of place and doesn't fit in at all. The ledge at the top looks silly, if it did have to be part of the design, it'd have been great to see PB make a feature of this IMO (maybe something similar to the cladding around Helix's station but in gold?)
The coaster looks fantastic and I like the theming, but it is a shame to see a poor station when it is something PB have done so well in the past.