Assuming you can edit your theme, you download both themes, unzip them, and splice in the featured post feature. (It’s probably in partials/featured-posts.hbs or something with a similar name.)
Sure! I’d probably start by looking for a theme that does that, and steal it’s partial file. :) (I’ve definitely seen it in paid themes, trying to remember if there’s a free theme that does it.) Basically, you need to do a separate #get tags and #foreach that loops over the tags and displays their count. This looks pretty close: Displaying the post count for each tag