I know many folks here are familiar with Cure Dolly already, but I wanted to share my recommendation for this book:
It is pretty short, but has a decent amount of depth - the premise is basically that textbooks try to teach Japanese grammar with a Westernised approach, and that if you view things slightly differently then sentence structure can make much more sense much faster. It’s almost philosophical.
I am still a rank beginner when it comes to grammar, but it helped make some things make much more sense to me, so I’d say it’s worth a look.
It’s available as part of Amazon Kindle Unlimited if you have that.