That big menubar on the top kind of reminds me of the elementary's website from Luna days. So my suggestion is to ditch it and use something more similar to the current design of the website:
elementary's logo left from the reddit's logo with a vertical line separating them. elementary's logo would link to the homepage of the subreddit and reddit's logo would link to the reddit's homepage.
On the right side of the menubar links to the most important elementary's links (which are now in the sidebar).
hot, new, controversial and similar could be in a separate bar below with only a vertical line separating them (so no boxes).
(If there's a way to do it) make the subscribe, shortcut and dashboard buttons bigger so they fit the whole width of the sidebar. I think that this is possible because the submit new content button is responsive and fits the whole width of the sidebar, so you could apply the same principle to these buttons as well.
Increase the font in the subreddit's description in the sidebar, which is currently much smaller than the font of the links. This makes the description kind of hard to read in my experience.
That big menubar on the top kind of reminds me of the elementary's website from Luna days. So my suggestion is to ditch it and use something more similar to the current design of the website:
submit new content
button is responsive and fits the whole width of the sidebar, so you could apply the same principle to these buttons as well.What do you think?