Before diving into detail please read my former question for further details:
Replacing a custom-developed CMS tool with SharePoint?
To sum-up, I need to create-develop a sharepoint site to replace some custom developed CMS site. The thing is, i will need some custom UI for managing content. Because as the structure will be sites and sub-sites and some contents in those sites, content authors will have to go to different sub-sites to add content. I think this is not best-practice, i think i should have some custom web parts or application pages, for content authors to easily add-edit contents for any level of sites.
I have sharepoint development experience, so all custom development ideas are welcome.
What is the best practice for these kind of CMS requirements in SharePoint structure?