A very good start; I like it.
I would give the topic list a little more padding for more breathing room. It doesn’t have to be quite that dense. As well as the tiger stripes already discussed.
Author and views aren’t things I usually look at when choosing what to view, but I don’t object to them being present. But the view counter does take up space that I think could be better used to present the tags and authors in a more orderly fashion, instead of being lumped in with the rest of the subject text, and making it more cluttered.
If all else fails, you could just replicate the old forum table setup and I doubt people would object.
I’m also reminded that, likely because of social media influences, or places like (eww) Reddit, there is a shaded blue box appended to the first post in every thread, with created/last reply/# replies/views/users/thanks/frequent posters, their avatars, popular links, and even an estimated read time. It’s collapsible, but can’t totally be eliminated.
A lot of that information is redundant, the rest can consume a lot of space, and on the whole, it strikes me as something to cram in social media-like information, and disruptive to the conversation.
Coming from the viewpoint of someone not invested in social media, or wanting to always know who posted, posted most, when, or what their avatars look like, I find the whole thing an element of unnecessary clutter.
The links may be useful, particularly for a commercial poster to utilize, or some form of wiki, but I don’t know if it’s editable, or strictly machine generated and can’t be user altered.
Within the thread, I’ll again advocate for strong distinction between each individual post, though it doesn’t have to be as severe as the old forum.
I’m also good with the overall color scheme, but the shading of the headings in the sidebar might not strictly be necessary, a minor point.
Otherwise, I can already see this being my default choice.