I will say that the interface and usability stuff is what would make me unlikely to buy even a really good expansion right now, because it's the most clear sign to me that the work being done behind the scenes is just off the mark. It's not a matter of little details being wrong, it's just another unsuccessful development attempt from a company that's started to make a habit of it.
I won't retread what a mistake it was to take all your development feedback from a tiny community of hardcore fans, 95% of whom are much more in love with spending hours building a structure than most of your market-base (or what that base could have been). Instead I'll just say that for a game that ended up being nearly entirely about building stuff, it blows my mind that the interface is like 1999-level bad, with menus and categorizations that make no sense, objects that can only be placed one at a time, walls that have to be manually built chunk-by-chunk, on and on and on.
It's like this game lives in a universe where props brushes and click-and-drag construction and intuitive menu design hasn't existed in similar games for a decade already. The interface has not advanced or improved in any fundamental way since the alpha cycle, and that's crazy. It's also a big reason everything feels so clunky. Creating and loading a single object for a 5 foot stretch of wall and then having to duplicate and manually place that object a hundred times to build a structure is just...an obsolete method. Ditto with the paths.
There's a reason other games have shifted to tools that let the player draw a structure outline and then the engine calculates the graphics and assets to fit it. It's not just easier, it doesn't just often look better, it's also a much better way to handle things from a technical end, and takes care of many of the performance and responsiveness issues that still plague this game. Instead Frontier took in-game construction mechanics from 20 years ago, slapped modern graphics resolutions and processing models on top of them, and the result has been predictable. And that's another engine-up problem demonstrating that they were just making poor decisions from the very start, unfortunately.
I wouldn't expect them to do a complete construction engine rewrite at this point, although IMO it's self-evident the game would benefit from it. But at the very least I want some version of this interface that doesn't start triggering pain points the second you open it up. If the only people "enjoying" your interface are the ones who've spent hundreds of hours in it and memorized all its nonsensical quirks and glitchy tricks then your interface needs to go. It's 2015-17, there's no shortage of instantly accessible, elegant, fun to use UI and usability concepts out there to draw inspiration from, but Frontier apparently did not.
All my complaints about the lack of content can at least theoretically be covered under the trusty ol' excuse of "oh they're a small developer they can only create so much," but things like the amateur hour interface are Design Foundations 101 at this point. There's no excuse. It was a choice not to meet the barest standards of modern design and technical architecture in many ways, and it shows. This company has big dreams, but very clearly finds it impossible to execute them to a high level at the end of the day.