I prefer external box makers, then import the SVG.
There are lots of posts about this, including this excellent writeup some genius (ahem) posted about a roundup of generators:
But for most things where I just need a simple box, I like this one:
I think that the more advanced stuff like boxes.py are overwrought for 90% of box projects, and I think the flourished corners on their output are unnecessary since we have clean corners. People love it, but I think it’s a terrible interface for just “make me a box”.