Early challenges in developing my Western Illinois underground railroad website

At present the challenges I face are trying to make the website more appealing to users. I would like to alter the font style and size of text on the website, and imbed some background images the website page header, but I cannot figure out how to do that in Omeka (though a website created by the Rosenzweig Center about the Russian gulag system used the same Omeka theme, and utilizes the kinds of stylistic aspects I aspire to for my site). I also would like to create a space on the website where users could leave moderated feedback. I think there could be appeal in the site’s presenting a sort of “fact versus myth” approach, but in order to do that I need to locate more items that lend themselves to categorization as a “myth.” At present there seem more mythical stories, memories, or beliefs about the underground railroad, than places and people, which are two of the exhibits that I have created. I installed a geomapping plugin and have plotted the locations of several items in the collection. I would like to plot additional places, especially any “mythical” underground railroad sites I can identify.