How to edit the TWENTY ELEVEN template to add a slideshow on top

I am using the Twenty Eleven theme on WordPress 3.4.2, I noticed that it has three templates, “sidebar”, “no sidebar” and “showcase”.
I am basically trying to have a hybrid between the SHOWCASE and the SIDEBAR templates. I need to have two “bodies”, or areas where I can put text and images, one rectangle just under the navigation menu, and one to the left of the sidebar.

I tried to realize this using the SHOWCASE template to do this, but I have to use the recent articles option.
This is the page that I made, https://www.potaporco.it

It would seem to work, but the problem is that i can only use one article on the recent articles page, for example, if I were to make another page with this layout, I would just be able to edit the slideshow, but not the body text.

So my question is this:
Can I create a page like the one that I put in the link, but with the possibility to create multiple ones with different articles?

Or an alternative solution that would work would be to use the sidebar template, but lower the sidebar of 300 pixels, so that I can place the image slideshow above it, like in the website that I linked.

Thanks ??