I am not an advanced user, but I think you can get modx working for you. You can go a lot farther with modx than you can with WP.
I spent just a few months learning a bit of html and css, so I am at about intermediate level. I did have someone turn a dreamweaver static site into a basic modx template though.
To me, its a balance between simplicity and power and control, to extend and develop the site. WP is fine, I have used it before, but it doesn’t give you a lot of control. Its advantage is simplicity.
Now I have a great deal of control over each and every page. I can adjust the sidebar at will, each section of the site can have a different sidebar if I wish. I just emailed my webmaster yesterday, crowing about how much control I have over the site. Again, I am not an advanced user, either.
Anyway, that’s my 2 cents. Good luck!
My website, still under development:
http://www.rayxi.com/index.php?id=1