Categories and SEO in Epik

I’m about to switch my current site’s theme to Epik. Can’t wait!
I’ve got hundreds of posts all nicely SEO’d and highly-ranked in the Goog, so I really don’t want to mess with my url’s. I would like to avoid writing a bunch of redirects. So here’s my question.

My current url’s look like domain.com/category/article-title/ … I’d like to keep this structure, but I’d like to change the navigation and the user experience.

Said simply, I want to create sub-home pages … essentially these would be category pages with widgets. OK, so here are my questions:

1) Can you recommend the best way for me to create a widgetized category template that I can use as ‘daughter’ homepages?
2) Assuming I’m successful in doing this, I believe my site hierarchy will remain unchanged: home->category->posts. Am I right?
3) I am going to need a Theme location to hold a custom menu for each daughter homepage. Can I create the theme location for the custom menu item within the custom template? I expect I’ll need to make multiple custom templates so taht each Theme location would be unique. Is that correct?
4) Regarding menus / nav … I’m wondering if it would be easier/smarter for me to just get a menu plugin, so that I can assign a menu to a specific (category) page. Your thoughts?
5) Do you see any problem if I use a menu plugin like ubermenu?

Thanks a lot!

DonO