When I transliterate to Python I am not, by definition, worried about performance. Python has horrible performance.
Ah, the "Pythonic way" of doing things! Like the "Steve Jobs" way of doing things, aka the one-finger interface. "Steve Jobs thinking" would bring us a "self-driving car" that we "drove" by tracing a finger along a moving map, clicking on stop signs to stop. We'd be singing about how marvelous it is... it "automatically" blinks the turn signal when we trace a finger along a left turn! Python is the "Steve Jobs" of languages and thought: so easy! so intuitive! so limited!
You ask "Are you sure your language of thought is really Lisp?". I'm also a mathematician. You're asking me if I think about math in terms of multiplication. I do, but not the way you expect. MY multiply can be non-commutative if I'm working in matrix algebra. It can be a map function in category theory. It can be limited to finite fields or expanded to octonions. I'm still thinking of "multiply"; I'm just not limited to numbers.
Similarly, when I'm thinking about a problem my "lisp thinking" isn't limited to symbols. I worked on a Human-Robot cooperative task to change a car tire. I needed a knowledge base...lisp (aka Scone). I needed rules... lisp (aka ops5). I needed human language... lisp (my own code). I needed it all to work together so that rules could be represented as knowledge and knowledge could be expressed as rules (all were defstructs). When thinking about the problem I could write "lisp pseudocode" and then simply execute it. If I needed "multiply" to be non-commutative in some section of code I knew I could make it work trivially. Indeed I didn't even have to think about it.
Thinking in Lisp has nothing to do with interned symbols, just as thinking in math has nothing to do with numbers.
Thinking in Python is like doing math on a calculator. Everything is "Pythonic", but just like your "calculator" in math, limited to numbers.
I think the reason people "don't get lisp" until "they get lisp!" (aka the epiphany event) is that they stop thinking in other languages and begin to think in lisp. A whole new world opens.