For even more justification of your decision, check out this fantastic presentation by Jake Archibald:
https://vimeo.com/145138876
Covers a lot of ground, but at one point he's exploring how to reduce page load times and web fonts turned out to take 4 seconds [out of 8 total] on a 3G connection. This was due primarily to the font hosting service (not necessarily the file size), so may or may not be pertinent to your situation... but really a wonderful talk if you're interested in these kinds of things.
My situation is indeed a bit different, since I'm hosting the fonts on my own webspace.
A big plus of Matthew Butterick's fonts: sane licensing. No need to estimate and document page views. No need to obfuscate fonts, in some vain exercise of thwarting font piracy. Just pay, host and serve.
I still think Equity Text is gorgeous, but the fonts are actually much bigger than any of my pages. Even the long ones with a few graphics.