Livecode is the commercial version. It used to have a community edition (free) but that was discontinued in 2021. The various other alternatives (Supercard was clunky and apparently doesn't run on 64-bit systems, PythonCard is dead, Shoes is effectively dead) besides Decker would be something like Delphi (ObjectPascal). There used to be a wxWindows-based system but that seems to have died also.
These days most folks would push you towards HTML / CSS / Javascript and possibly Node.js or Deno. In my mind Hypercard was the bridge between desktop programming and web development. Realistically that's not really bad advice.
For desktop programming, Dart/Flutter (Google recently laid off parts of those teams) are viable as are Python/Kivy (or even Python/Tkinter since Tkinter comes bundled with Python). You might also want to look at the DragonRuby Game Toolkit (Ruby).
Best advice I can offer is know your limits and that requires knowing how and when to say "No". Others have mentioned raising rates, and that works to a degree, but ultimately you have to be able to say "No" when your capacity is maxed out.
These days most folks would push you towards HTML / CSS / Javascript and possibly Node.js or Deno. In my mind Hypercard was the bridge between desktop programming and web development. Realistically that's not really bad advice.
For desktop programming, Dart/Flutter (Google recently laid off parts of those teams) are viable as are Python/Kivy (or even Python/Tkinter since Tkinter comes bundled with Python). You might also want to look at the DragonRuby Game Toolkit (Ruby).