Well, now I have no regrets about buying a Nintendo Switch.
On another note, while I don't know much about japanese, I think the game's title is to be translated as "Shinobi Refresh Senran Kagura". The last three katakana (I think they are katakana, at least?) for "Shinobirifure" (シノビリフレ) are the same that are used in Pokémon Sun and Moon's Pokémon Refresh's japanese name, "Poké Rifure" (ポケリフレ). So, judging from the title, this will probably be just an expansion of the Dressing Room. Although I personally think that this is made in order to test out some new features with the HD Rumble that we might see in future games, perhaps even in Senran Kagura 7 if it will come out on the Switch.
I guess that indicates the budget this game is working with...
I'm guessing this to be a technological investigation in the Switch's possibilities more than a fully fleshed out game. After all, the interview says the idea is a digital only Asuka only game, from the company that #1, seems to love Yumi more than anything (of course, they judge by fan reception, but still. Perhaps it is an indication they may not bring Gessen and New Hebijo to Nintendo though), but more importantly, #2, had limited edition pre orders announced before actually explaining the game. A digital only game then really feels like testing the waters, perhaps technologically, but perhaps also for their demographic. It'd be the first moe release on the Switch, and they may be unsure how many Senran Kagura fans even own a Switch now, and a low budget/small commitment release may be a better way to test the market than a research.
Takaki just tweeted out this photo of the main menu for Shinobi Refle. There's a line of text down at the bottom that says キャラクター選択, which translates to "Character Select". I think we might be getting more characters than just Asuka.
He mentioned in an interview that it'll be Asuka only first, but he wants to include kore characters. I'm guessing it'll depend on how well it does. There'll probably be the usual character popularity pollsnto decide who'll be added. My guess at least.