Thanks for the report!
The Hakkaisan Tokubetsu Junmai is an affordable bottle of sake retail and maybe you can find it at Nijiya for $20 or less, but it does come from a successful large scale production brewery in Niigata (along the lines of Kubota). It’s not too boozy, but it also doesn’t have a lot of character compared to smaller artisan breweries that do Tokubetsu Junmai type sake. To me it’s very middle of the road, approachable to some degree…but you’ve been in touch with the Dark Side Of The Force (tip of the iceberg) with the Tedorigawa Kinka and Amabuki Strawberry…so there is much more to explore!
It’s also possible that the Hakkaisan bottle has been opened a while, and some sake don’t age very well after opening, even in storage. Some more or less stay the same (flat). At least you didn’t have to pay for the flight.
For a Tokubetsu Junmai that will cost just a little bit more on the menu, try the award winning Nanbu Bijin at Raku (have a taste first before you commit) that’s a touch on the aromatic side. I recently paired NB with tonkotsu ramen from Ippudo and it strangely works quite nicely. Or try the ever sturdy Urakasumi Junmai that’s very classy and well structured and balanced that also goes well with sushi. Though with a sashimi starter, the Kokuryu Tokusen Ginjo is the way to go (a glass or carafe), then progress to the Junmai.