If you want to have an animated intro, make it interact with your actual UI; introduce options, start playing immediately, show cues for discovering additional features.
Also, it doesn't feel natural to have to click the 'hamburger' icon on the top right, when the first introduction to the navigation is invoked automatically and spans the entire width. I keep going back to it to change settings and it's not intuitive.
The reason why the menu is automatically shown is precisely to let the user know, on start, what options are hidden behind the hamburger menu. Do you mean the positioning is weird or that it shouldn't be shown automatically?
I think showing the menu automatically is great, just that when I go to re-open it myself, the button at the top right does not feel natural. I know there was a panel there, so my natural tendency is to scroll or move the mouse cursor in search of it.
You've only got a few core features, so you've got more creativity available in how you present them: On desktop you could reveal the nav when the mouse cursor is in the top 100px, and on mobile show it when the user scrolls to the top. No clicks or taps necessary, because there's nothing that would conflict with that behavior. Consider something similar for the player/info panel at the bottom. When the user stops interacting for a second or two, slide the panels away and show only the visualizer.
Curiously, I don't normally click on the hamburger icon because hitting the ESC key also toggles the top menu, so I completely agree with you that it doesn't feel natural.
I've been tempted to put more information on the player panel but have forced myself not to do so to keep the UI as clean as possible (mainly thinking in mobile browsers). I guess I could put in some icons, though, that would give hints to user as to what's actually going on behind the scenes.
Minor problem though, since you can skip the intro.
This is actually a long topic because Muki contains a mixture of ripped vs sequenced tunes, etc. I've contacted some of the authors of sequenced tunes for permission, and also taken great care of crediting both the source where I got each one plus the company who holds the rights for the original tune. You can see this by clicking over a song's name when playing.
That said, I'm definitely not an expert on copyright so if there's something I'm missing please let me know! There's also more info about this if you click on the "about" link.
Is there a way to disable the dots so the browser stops murdering my CPU?
I guess you're right. YouTube already hosts a ton of game music videos and they don't seem to have any problems.