Is the math what matters to you? Do you make attribute, skill and other choices based on what is 'best' or do you choose what is thematically appropriate for your character?
IMO there are different situations to consider...
1) If someone comes up with mathematical proof that e.g. a Paladin is stronger than a Ranger, I don't care. I play a Paladin if I want my PC to be a Paladin and a Ranger if I want her to be a Ranger. Furthermore, it's practically
impossible to really compare things at a higher level, because of the complexity: what does it even mean "stronger" when comparing classes as a whole? Whatever criteria for the comparison, it's always narrowed down to one aspect of the game only. Unless there are enormous differences, math doesn't matter to me in this case.
2) If there are 2 alternative (narrow) choices one of which is undoubtedly better than the other, then it does matter to me, and I tend to judge negatively the game design in this case. For example, if there are 2 weapons which are
completely identical except for 1 parameter, then picking the worse weapon makes me feel stupid, and I don't like that...
It doesn't matter if it's a minor parameter. Do you know when you go to a supermarket and you notice that there are 2 copy-products, usually one just has the label of the supermarket brand and costs a little less than the one with the label of the real brand (but then you look at the back label and clearly see the manufacturer is the same, the content is the same, and even the container is exactly the same except the label)? Then it's just plain stupid not to buy the cheaper one.
And the image doesn't always matter, because you can change the image of anything in the game. The book may say the katana is exactly the same as a b.sword but costs more, fine I'll take the b.sword and call it a katana.