Numbers 26 and 28 are very elegant and clean, which I like. I don't think that the placement of the 2 allows for it to read J squared. It reads J 2 as is. I'd love to see these options looking more like exponents. Although I love the font of the J, I don't think it would be easily recognized as a J. I'd also love to see a different font (though along the same lines) that is more noticeably a J. Thank you.