First of all I love LaTeX/MathJax; I use it a lot, but there are couple of things I hate about it. Sometimes the code becomes so messy that I almost can't read it without looking at the output, while I feel like the code could have been much cleaner.

For example, sometimes you have in a sentence many `\left`'s and `\right`'s. I don't understand why LaTeX wouldn't interpret `(` as `\left(` and `)` as `\right)`? That would make such code a lot cleaner.

Also, things like: `\int_a^b \! f(x) \, \mathrm{d}x.` I would like to type something as `\int{x,a,b}{f(x)}`. Instead of memorizing what to type to let things look good. 

Are there maybe packages that would make me able to write "cleaner" LaTeX code?