Hi there
I'm the developer for SteemPower and i'm glad you found it useful.
Since you posted this review a new version of the site is out with some cool new features so please check it out and let myself or Charlie know what you think - and even more new features are coming.
On the subject of emojis, this is a feature of the markdown editor component we're using and is disabled by default. Unfortunately steemit.com does not render them and so I haven't turned them on. I'll look into a way to get them rendered as images or disable that button.
And last but not least: The current version of the editor has a menu bar with Load and Save options under File. You can currently store a single draft and come back to it later - just make sure you do so from the same browser. This feature depends on HTML5 LocalStorage so the draft is stored entirely on your own machine.
At the risk of repeating myself: thanks for reviewing the site, and keep an eye out for what comes next.