How do you adjust the distance between lists and text?

As you can see in the image below, there is too much gap between paragraphs and lists. It is also true for equations that are centered in a line and for the distance between a level 1 list element and a level 2 list element. How do I adjust this spacing? I am looking for a global solution, using vspace for each one is a daunting task that also messes up spacing further.

List of packages employed can be found here.
In this particular case, there is no point in sharing the document as it is just a simple list with no modifications.
Removing doublespacing results in saner gaps but I need double spacing. Is there a way to add double spacing so that it does not affect the gap?

.tex File