Looking for a "custom" script editor

[metulburr]

I dont know i dont use sublime text. I didnt really like it.

it just overwhelms me a bit having to create custom "build systems" just to run code

I am not sure what you mean by custom "build systems" to run code? You install python3.7 on your system, and point whatever IDE/Editor you use to to its interpreter. I would bet that there is a way to modify where that editor points to, but i dont have it so i cant play with it to try. IF you can find where their python interpeter resides, you might be able to replace it with python3.x, or a config file to change the path to the interpreter.

still haven't figured out how I can execute python code without working in a saved document.

The only way i know how to work with python without saving on hard disk, is web. Stuff like this.

if you know of a good way of executing highlighted words/lines

What you are talking about is called selective execution. Maybe google that for IDE's that cover that.