It really depends on your target audience as well as the medium important to them. If it is all about content, then have a theme that really focuses the main part of the page on the post itself and not really the sidebar. If the target audience is really important in the posts as well as the things you have in your sidebar you might want to lean towards having a theme with multiple sidebars. As for user friendly, I don’t really have a personal preference on any particular theme that is available here. I have seen great applications on all of them.