So someone on github thought me a much easier hack to make the peertube homepage any page we want, without touching the nginx config at all. Here's how simple it is: you log in as root/admin on your peertube. Go to "configuration" and where it asks to select the landing page, right click that and then "Inspect Element". You'll see this:

Now select the "option" for say "Local videos" and edit it in that window and replace the "value" with any url you want. Now select that option in the Configuration and click save. That's it. You tricked Peertube!

Again: the idea is to change the value of any of the selected options in the Landing Page dropdown to any URL you want, and click save. Brilliant! #tromlive