Please stick to a font already in my browser. My network is slow and webpages sometimes get stuck loading; the resources in your page took 40 seconds to load and your font didn't even load yet.
Testing a big more, just dropping "dlig" from the feature settings declaration turns off the awful st ligature. So they don't have to 'all' be turned off to get rid of that one. What I don't know is what other ones get turned off by dropping "dlig" from the declaration.