I use MERN stack - huge community and libraries for everything. I like the "everything as JS" approach I can take with React as I never liked jumping between html/js/css.

Additionally, I found Firebase to be a really great way to start and run projects. The most important piece of that is Firebase Auth which solves a complex and important problem without costing an arm and a leg. Other services such as Hosting, storage, and functions were really easy to start with.