There are many more success non-popular stories around DSLs. Last year, in the Community event of JetBrains MPS, a bunch of big companies (Siemens, Bosch, Workday, etc.) showcased their DSLs built with MPS technology. Here are the videos: https://www.youtube.com/watch?v=102hoaAdctk&list=PLQ176FUIyI...

I think you should definitely take a look to Meta Programming System (MPS) from JetBrains: https://www.jetbrains.com/mps/

We should not be constrained of only text notation, so a technology like the projectional editor of Jetbrains mps should be there. https://www.youtube.com/watch?v=iN2PflvXUqQ