We CAN say that one way is absolutely better than the other, so long as we can back up our reasons for doing so rationally.
Your reasoning is in line with what Epistemology calls Skepticism. That is, you are suggesting that different viewpoints are not any better than the others, they just are "different". A higher level of reasoning beyond Skepticism is Rationalism, whereby, simply put, you identify different viewpoints, but realize that no things are completely identical. So you commit to choosing the better one, and back up your decision via compelling, rational, reasons.
The blocks vs streets is a good example. I could come up with very compelling reasoning to suggest how naming blocks is far inferior to street names. But to suggest something to the effect of "Neat. They both are great and no one way is better than the other." is idealistic and a cop out from an Epidemiological standpoint.
It's *OK* to say that we have a superior system sometimes.