Shameless plug: I'm working on a [Text GUI library](https://github.com/Hexworks/zircon) which has the option for isometric projection [like this](https://cdn.discordapp.com/attachments/205245036084985857/41...). It is completely decoupled from the backend (the simulation engine in your case) so if you are interested we can work together. I also work in Kotlin and I'm eager to put in some work to create a fun game. It also supports tilesets so you are not stuck with ASCII.
Just nitpicking, but this is not isometric, this is top-down oblique projection. Isometric is when all 3 axis are of equal length and separated by 120 degrees.
I think you're technically correct, but 'isometric' is also a pretty widely used non-technical term when describing video games which have some form of non-perspective 3D projection, even if the axes are unequally foreshortened.
Very cool! If you could play this in terminal it would be awesome. We could be a good testbed for your ideas -- we have kept the simulator separate from the UI / display.