MODx is very flexible and can accommodate any design you can dream up so yes, you can have sub menus and pages like in your example. You will have to learn the system in order to put it all together but as someone with a php background that should not be a big problem.
I say go for it and welcome to the community.
Wayfinder can output top level menus with the matching sub menu.
Ditto can create News summary boxes.
Both these snippets are included as a matter of course.
If you install Modx with the demo content you will be able to see them in action.
