How much code are you writing within WordPress? The html view is just for fine tuning the content of your posts, if you are doing any more than that then you are doing it wrong.
If your posts and pages don’t look the way you want then create some new templates in your editor of choice and apply them as and when needed.
Number of templates depends on the scale of the site. A simple portfolio could probably have about 5. We have developed our own CMS for the company that I work for and some clients have up to 17-20 templates for many different uses.
If the coding is very complicated (which defeats the purpose of the CMS), why don’t you just code it in DW (or your choice of editors) and then copy/paste into WP?
Well I’m trying to use WP as a type of CMS… You see, basically inserting the content through the source part and just using the php includes.
That’s one strange type of CMS.
The whole point of any CMS is to be able to add/edit content without having to write code, that’s why it’s called a content management system. If you have to code a new layout everytime you want to add something then it’s just a website.
You could try integrating this into your backend http://markitup.jaysalvat.com/home/
Okay then, so how in WordPress could you control all the different "modules" that you want to appear at different parts on the pages like other CMSs then? Code the sidebar to not really be a sidebar and just another div somewhere?