An important quality of a professional software engineer is being able to work in a team and being able to deal with personal differences. And those difference go beyond coding styles. With respect to coding styles, I always tell junior software engineers to not change the code formatting, the names of classes and methods, and abstain from refactoring code just fit it to your preferences.

My personal preferences is to keep the code base as small as is needed for the moment. I avoid creating functions/methods that are only called once. If possible, (like in C#) I prefer using local methods and lambda expressions. I try to avoid code dupplication (beyond the trivial). I am carefull with introducing abstractions as often it makes it harder to navigate and/or debug the code.