Looking for Drupal modules for formatting the output of comments on content and creating galleries

To improve my webmaster skills, I started creating a website. This is my second “hamster” (project), the first was made many years ago with plain HTML+CSS; for this one I’m using a PHP CMS (just to say, I’m a newbie but not a complete beginner). The plan is a blog site whose design should resemble the interfaces of popular social networks like Facebook and VKontakte. It should support anonymous commenting on posts and photo uploads.

After trying several CMSs, I settled on Drupal 7, which immediately provided the necessary functionality through the standard Blog and Comment modules, allowing me to create a blog with anonymous commenting capabilities. Then I installed the Metatag, WYSIWYG, and Views modules, which gave me a convenient posting interface. Using Views, I created a view that displays the blog without titles by rearranging the field order.

Now I want to further extend Drupal’s functionality with modules, and here I ask for advice on module selection:

1. How my site looks now can be seen from the attached screenshot. I want comments on content to be displayed not on a separate page like node/1, but directly below the content. Which module can implement this functionality? Maybe there is a Views extension for this?

2. I need a convenient interface for working with images. I created a content type "Image," but that’s not enough. First, I need to upload multiple images at once, not one by one. Second, images should be categorized into galleries, not just dumped into sites/default/files/private, or else it will be a mess. Third, each gallery should generate HTML code for embedding in a "Blog post" content type. I tried Media Gallery, Brilliant Gallery, and Multiupload Imagefield Widget — the first is buggy and insecure, the second doesn’t work at all, and the third lacks features. Please suggest a solution.

3. I would like to add the ability to play video files directly on the page, like on YouTube. Is this possible? I understand this task may be complex, so I’m ready to postpone it until the first two tasks are completed.