Please. Coffee has its problems, but being white-space sensitive is not one of them. It's entirely a matter of personal preference, just like preferring {...} instead of begin...end or using '' instead of "" for strings; it's not even as significant as prefix vs. infix syntax, which does have some practical consequences. You get indentation based blocks in quite a lot of languages, Haskell, F#, Python, Nimrod, MoonScript and others and it works there, I see no reason (knowing them all) for it to be a problem in Coffee particular case (to be honest, Coffee allowing inconsistent indentation in a single file is a bad design decision, though).

You aren't likely to see this again, but in case it helps, the following setting in Sublime Text's key bindings may help you:

``` { "keys": ["super+v"], "command": "paste_and_indent" }, { "keys": ["super+shift+v"], "command": "paste" }, ```

Though you should always be careful when copy/pasting code.

I'm not sure how it encourages classes, I personally didn't even use classes at all for the first long period of my CoffeeScript life. And now only do sparingly.