Please, estimate the operation of engine for site

All the pages are made only in HTML, and there is only the text of central column material; building of menu and of other things, display of CSS styles are performed with Java Script, it should be put at the beginning of HTML page and it does everything automatically, design of site is built of separate file with pattern, there the design can be changed within two hours for all the site.
The engine itself is only 4К. The rest is pages, styles, pictures of pattern.

What do you think about such a solution of the problem?