I found out later that it wasn't, (instead a sequel to Touch) but the art style was so nostalgic I stayed for the whole thing.
The reason I give this an 8, although I probably should have given a 7, is because I feel it gets more hate than it deserves. Writing and story aside, the animation is top tier, so good I thought it was Production IG for a second. The music isn't at all irritating, as it can so easily be in shows like this, and the fact that Mix was created with such love and care made me want to rate them as such.
The reasons to watch Mix are the following: if you love baseball anime (despite it being repetitive at times), if you like slice of life, and if you like calm, realistic main characters (the side cast leaves something to be desired). Oh and if you like Kaji Yuki.
It's animation is absolutely fantastic, never once dropping because of it's classic art style. I watched it all the way through, and while I definitely prefer Diamond no Ace, Cross Game and Major faaar more, I still enjoyed myself massively.
But Mix wasn't without flaws. The baseball aspect was very stereotypical (but at this point in sports anime, how can it not be?), and the supporting characters were extremely bland, contributing nothing to the team. And then it's whole sister-obsession. The show focused ridiculously on Otomi being some curvaceous, voluptuous icon, where she was only 14.
Also, be warned, those who have issues with Eren/Mikasa pairing (although when the started to live together, they were 10, well aware of their separate upbringings) will definitely have problems with the main 'couple' bordering on incest. Thankfully, the show doesn't focus too much on it at all, and one can even shrug it off by saying it's brotherly love. But honestly, at 5 y/o, you don't really notice that you're from separate parents. I don't have a step-sibling, but I'm sure that being raised from 5 as siblings MAKES you siblings.
Oh Japan. Of course if that's your cup of tea, more to ya.
Regardless, I found refuge in Souichiro, the 'twin' brother. But I still liked Touma plenty.
Bottom line: give it a chance. If you like it by episode 3, you'll like it throughout. But if not, don't continue further, because it's more of the same.
