Ill counter that by saying that because you started with something more low level, the other stuff was easy (my belief).

Also, depending on what the students are actually studying, I think you need to give an introduction to low level stuff because while some will want to do web dev for example, others might want to do low level stuff. Obviously if its a web dev course you dont want to do that, but if its something like CompSci or Software Engineering then i think having a grasp of the fundamentals of low level stuff is necessary.

Lastly, if its a general introduction to programming course I think C has advantages over other languages since almost everything is done by you, instead of the compiler (for example iterating over an array - C: you need to do the for loop to manually handle the data depending on whatever type is stored in the array - Python: for x in y is sufficient). Im tutoring my little sister in programming because they have it in school, and they use python. Sure its easier to get things done, but its harder to learn/teach general programming with python in my opinion. C would have been my choice, especially since at that level its not like you need to teach/learn memory management, or complex data structures. Its the same concepts as with python (input, output, variables, conditionals, loops, functions) but the syntax just doesnt hide too much frlm you, unlike python