I am totally in love with most of the above, in fact, I was trying to do that a long while, but fell flat on my face when I saw the state of the calendar rendering.
There is so much hardcoded and fugly HTML in there, I just stopped. Also, real life demanded that I finish my studies first. Now, with the last part, I am almost done, I hope.
You can see my hacking around in the layout_rework branch in git, but this is kind of a timetravel since it is really old. You might get an idea what I was trying to undertake then. I almost threw out all pre-existing html and I threw out all css. I did not touch the js then, though. I also used a framework, but it was Amazium http://www.amazium.co.uk
Amazium has the benefit of not using any _javascript_ for layout, since the things we do with the content is already using js enough, I thought adding an additional layer might not be wise. Also, it does not come with all the hipster shit like less/sass/etc. which is trying to improve your code before delivering. Anyway, it worked well enough for me so that I used my layout_rework as a frontend for this very uncensored citadel here.
Thinking about it now, I guess if we start all over again, I would consider the following things:
1. Go all the way to HTML5. We probably won't be rebuilding everything all over again soon, so we should aim for a solid and future proof base.
2. Less is more. I like the idea of having a framework that eases UI development. I do not like the idea of having to learn a whole new UI language, only to find out that the developing hipsters throw everything overboard next year in order to come up with the next hip thing. So it should be as close to regular html and css.
3. Less is still more. I am all for using jquery for the js stuff, seems to be one of the more sane choices. scriptaculous is too old and untimely. But I also do not want the layout framework to be dripping js all over the place. The mail rendering, the calendar stuff, the mail editing will probably bring along enough code by themselves and we should aim for snappy.
4. Then we have to agree on the looks. It might be unwise to bring in apple as an example, but just as they dropped sceuouemörphism from their devices, we should drop a lot of the stuff from the citadel UI and focus on the UX. We probably should hide a lot of stuff which is currently visible and rearrange other things around. People know how a website works, they are used to messenger interfaces like gmail, gmx, facebook, twitter and whatnot.
Personally, I like the looks of http://qz.com/ and a lot of the minimalistic black and white layouts that architecture/design nazis use.
5. We should also think about 4k and other large resolutions. Even on 3k displays, most of the webpages look lost. I'd like to include a widescreen mode, so that we can really make use of all the real estate there is.
I might think about the more technical issues later.
