Thanks for the suggestion! I've considered using and learning Twine and have heard good things about it. I didn't come across Sugarcube specifically and scanned through some of its documentation with interest.
It's still early days and I wrote this post before finding alternatives to ink, so I'm glad you highlight these for any other authors looking to port projects onto their own sites or utilise other features the reasonably powerful (but still limited) editor on this site.
. It can be done apparently, but requires some stuff I don't understand yet. The article basically outlines how to create an inventory system UI that's present at all times at the bottom of your screen and allows you to use items whenever you want on top of whatever choices are available (it's a more flexible version of this site's native item system).
If you know how to do this in Twine or have seen something similar, I'd be very interested!