Cool! And yeah the breakups are actually also used commonly with specific affixes. Like the witch doctor might have an affix that provides a bonus to "spirit skills", which would be skills specifically in the spirit section of the skill list.
We plan to have a fairly robust pop-up tutorial system as you acquire new features to guide players through some of the games systems. Explaining the cauldron and nephalem cube as well as interacting with and using an artisan for the first time are great examples of where a tutorial is probably needed. The game is pretty intuitive but there are those minor bumps, and we think the tutorial system will be plenty helpful in addressing those issues.
For instance, when you level up for the first time a tutorial bubble would point to your skills panel button, clicking on that you'd be guided to click on a skill button, and then of course shown your choices.
We really like the UI as-is because once you get over that really minor first 'click on a skill to change it', it's very obvious and useful in the way it's laid out.