Humility? The best engineering is engineering that doesn't reflect the engineer's ego. Great engineers are great because they maintain a focus on being good engineers.
For example:
Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian Kernighan
Good luck.
For me, leaving a plateau usually requires a paradigm shift. Here's a few rabbit-holes for you:
• Learn memory management from Rust
• Study Postgres internals: https://www.interdb.jp/pg/
• Learn architecture and design from Elm: https://taylor.town/elm-2023
• Try building things "from scratch" with zero dependencies
• Watch online lectures from Joe Armstrong, Alan Kay, Gerald Sussman, Bret Victor, Casey Muratori, Greg Young, Richard Feldman
• Build a robot
• Learn a semi-esoteric language like Forth, APL/J/K/BQN, Lisp/Scheme, Wolfram Language, etc.
But research isn't enough. I never really understood the value of new paradigms until I tried to use them in a personal (or professional) project.
Let me know if you need any further resources or suggestions.
Good luck!