I really appreciate you having Japanese as a language choice. I've been dying to hone my japanese skills with AI in lieu of reading grammar/vocab books etc.
I definitely intend to use your product more, because it is definitely scratching that itch!
A couple of things that might help me personally would be the ability to cancel my current response and redo it, as frequently I will stutter or pause on a thought and wish I could restart over.
In that same vein I would love to see the output of what I'm saying in real-time. If only to gauge and understand what the application "thinks" I'm saying and to potentially correct and miscommunications from spoken input.
I would also love the chance to role play or have the tool help me learn contextual role playing. For example in Japanese keigo is a skill I just haven't mastered. I would love a tool to help put me in positions where I need to use keigo, and then be corrected where I'm failing.
Regardless, this is absolutely fantastic! Thank you so much for sharing! You're awesome :)