I recently re-read this, I think for a second time, and I've just got to admit this is absolutely perfect. It's all Adachi. The recycled character designs, the usual stereotypes, the slapstick humour, the 4th wall breaks, the cameos, the tragedy, the completely predictable storyline, the happy ending. And it works.
Adachi has written many high school baseball/romance manga but the structure has stayed pretty much the same since Nine, published 27 years before he began writing this. And shortly after Nine he started with what many consider his masterpiece—Touch. Touch's cultural impact and recognition even today is big. Can't say the same for Cross Game. The timing of Touch's publication was better. It came at just the right time to be a big hit. In some ways it was also better. The tragedy was more well timed and more impactful. There was more character development and it was more gradual. The characters were more unique and memorable. But it was also more serious in tone. Cross Game is lighter and doesn't take risks like Touch did. It's also a lighter read, which is what you'd expect when picking up an Adachi manga.
But Cross Game is where Adachi's lifetime of experience came together. This is what he failed to achieve in Nine, H2 and even Touch. And later with Mix, which unfortunately doesn't live up to Touch (which it's based on). It's not a perfect manga by any means, but perfect Adachi. And one of the most realistically depicted tsundere love interests in manga.
Cross Game is definitely Adachi's best work. I'd still say Touch is my favourite but that might be in part because I read it earlier and during a time in my life when it had a bigger impact. Definitely recommended reading.