Yeah, see, this is exactly what I was afraid of in terms of expanding the game. She's talking about taking away elementals to introduce them properly in a later quest. So in other words, not adding to the game, simply taking what already exists and spreading it out. One of the things I love about LT is how concentrated everything is. A lot of games in development are like that, with all the mechanics and systems already present in a very compact package that's a ton of fun, and then the later stages of development basically consist of adding more filler and diluting the experience.
Its unfortunate, but I also have to recognize that LT, for all its bells and whistles, has always been a bit too ambitious for a single person to tackle. Inno refuses to hire a team so dedicated help is out of the question as well. LT was and still is her first game - when you start off you have a very naive perception of how things work, what you're capable of, and how much time it really takes to get things done. She has had 4 years to get some experience under her belt and realize some "fat" needs to be shed off in order to deliver a better, more compact experience... and increase the likelihood of it ever being finished.
For all the praise it gets, one of the most common complaints is precisely about as "wide as an ocean and as deep as a puddle" it feels. There are a lot of mechanics in place yet only a handful of them have any meat to them, so to speak. For all the morphs that exist, how many are truly recognized by the game? If we visit Ralph, Finch, or anyone else as a human and later as a demon, do they say anything? Aside from the demons and half-demons directly related to that quest, does anyone say anything about our transformation? No. Some of the fetishes in the fetish window do absolutely nothing and are impossible to level. And leveling those that do work changes nothing in your game.
Another complaint I've seen is how little incentive there is to step outside of Dominion, as everything is basically concentrated in the starting area. TiTs used to have a similar problem as well - the early game felt rich and detailed but the further you went the more barren it got. This doesn't mean she's not going to make more content like you say, but it does make sense to spread some of what she has already done to future areas. Centaurs, for example, were released early partially to facilitate the implementation of ferals, which are coming up during the Foloi Fields area. This may also be why the game feels so wide and shallow, as she starts by adding a lot of features and mechanics early and expanding them at a later date.
Are more things going to be scrapped in the future, as you suspect? Maybe. And as unfortunate as that may be for some, I'd rather have quality over quantity, at least for the official release. You are free to mod and jack up your game once the modding templates are released. For now, Inno has made a fundamental step in realizing her limitations and making a tough decision to let go of one thing to benefit other parts of her game. We're still going to have temporary companions, like Claire, but in exceptional circumstances.