So, who has the time and wherewithal to write up a comparison between Ink and Inform7? I anxiously await your blog post :)
Ink is most similar to ChoiceScript [0], which powers Choice of Games's Games. Twine [1] has the same structure but is a visual editor, not a scripting language. Undum [2] produces the same kind of system, but is Javascript rather than its own syntax. Dendry [3] powered Varytale's games, but the open source version seems abandoned. For completeness, though a webapp not a language, StoryNexus [4] is a hosted platform with a database-like interface (fill in a bunch of forms), it powers Failbetter's Games.
Inform7 is very impressive as a natural language syntax. But the kinds of 'parser' based games it is best suited for have always been rather niche, because they require a certain familiarity with the form.
[0]: https://www.choiceofgames.com/make-your-own-games/choicescri... [1]: https://twinery.org/2/#welcome [2]: http://undum.com/ [3]: http://dendry.org/ [4]: http://storynexus.com/s