uMatrix not only allows you to block JS on a site you're visiting, but gives you fine-grained control over blocking JS from sites that site calls out to, and subdomains of that site as well.

I find uMatrix much more flexible than uBO in this regard. I don't even know if doing all this is possible in uBO, and suspect it's not, or that at least it's hidden away pretty well, while this is front and center in uMatrix's interface.

You can do some of that with uBO (see "hard" blocking mode), but my understanding is that uMatrix gives you more granular control. I need to learn more about using uMatrix to confirm, though.

I use uMatrix for that. I like the block/allow interface.

Off topic: if I use uMatrix should I still be using uBlock Origin as well? Or does uMatric encompass all the features of uBlock and then some?

That's what I do, too.