Yes, there is at least one downside to MSDF among a set of possible downsides (huge atlas, or dynamic rebaking, or limited glyph set), and the article is written as though they all apply, which is a bit misleading. Slug is cool, glad it exists, but it isn't the right fit for my rendering project either.

I did a similar one recently but have not been able to validate it's calculations against any other source. Thanks for posting the link to yours when I get time I'll compare and see if they match up. https://git.mikedilger.com/mikedilger/sunangle

The solution to bad relays is to just use different relays. Changing your relays is just a matter of publishing a new 10002 relay list, and optionally copying over your old notes (or reseeding them from local backups).