I just tried to use the editor again; I was going to open jsfiddle but said why not. There is no way to create a new file. I remember a while back you could at least preload a bootstrap template. All in all, I still like the editor interface but there needs to be a few controls.
The only issue with a 'clunky ui' is the homepage but that might just be a side effect of bootstrap.
On that note, I'd also like to be able to load more frameworks than just BootStrap. Here are a few suggestions:
[1] http://foundation.zurb.com
[2] http://www.getskeleton.com/
[3] http://blueprintcss.org/
[4] http://960.gs/
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