Ok = I've looked around a lot for a clear answer to this, but find very few real answers. I would really appreciate some info from experienced individuals.

A tiny bit of background. I've worked content generation (among other thing) on a largeish website for many years, and it follows the pretty basic file system and discreet html (.aspx) pages for content. You want a new page, you make a new file and build your content. Done. I've built a dozen or so brochure sites like this as well. This is the system that makes sense to me, and I find myself a little hesitant to veer away. 

CMS systems, like WP, obviously do not work like this. I am not inexperienced with wordpress. I've built and implemented a couple custom themes, but have "tried" to make the above file structure work "along side" of a wordpress install - mostly leading to headaches.

That is where I currently sit, having spent a couple of months of weekends building my new personal site (which is almost finished). The format of the site is pretty straightforward - its a developer blog (I do a lot of AS3), a portfolio for artwork, and a main intro page that contains a bit of both. 

My file structure looks a bit like so:

     mysite.com-
         /css/ 
         /home/ 
         /images/ 
         /javascript/
         /portfolio/ 
         /php/ (holds a lot of php snippets that is included elsewhere)
         /swf/
         /wordpress/../theme/ (draws upon img/css/php in external folders)
         index.php

While I do very much like the familiarity of this structure, the cross sharing of assets between static files and dynamic wordpress content is a pain. My option is to turn all static files into templates, and make use of WP's database driven page system. 

What do I stand to gain from "buying into" the WP system completely? Or, conversely, is a static file structure external to wordpress "workable" - and are there preferred methods of doing so?

I realize this question is somewhat subjective, however, the proper handling of static content is, I think, a quite valid point of inquiry (tho... you might not think it, considering how little info there is to be found on the subject). 

Thanks