如果部分位于列表之后，则避免 vspace 中的额外空间（以及与 enumitem 相关的问题）

Question

1. 为什么当我创建一个新的长度并将其设置为时\parskip，它会变成 0？（参见 MWE 的前面部分）
2. 我希望列表显示在文本正下方，并在其后开始一个段落。这样做时，如果列表后出现一个部分，则间距太大；我相信是因为我after=\vspace{...}在 itemize 定义中使用了它。
3. 有没有办法设置某种软垂直跳过？或者也许模糊是正确的词。如果后面除了节之外还有别的内容，请使用\parskip，如果后面有节，请尊重它想要的跳过？
4. 如果列表出现在某个部分之后，我需要使用它before=\hfill来确保列表具有适当的间距，为什么？我不是在空白行上使用 \hfill 吗？也许这会将 LaTeX 更改为水平模式？否则列表会告诉它进入垂直模式吗？

\documentclass[parskip=full]{scrartcl}

\usepackage{printlen}

\newlength{\ParSkipAmount}
\setlength{\ParSkipAmount}{13.6pt plus 1.36 pt}  % determined by baseline skip
%\setlength{\ParSkipAmount}{\parskip}  % why does this go to 0 if I uncomment it??

\usepackage{enumitem} %
\setlist{nosep}  %
\setlist[itemize]{
    topsep=-\ParSkipAmount,% removes parskip, 
    before=\hfill,  % makes top of list appear in correct spot after section
    after=\\}% this cancels topsep

\newcommand{\examplelist}{%
    \begin{itemize}
        \item One
        \item Two
    \end{itemize}
}


\begin{document}

    \uselengthunit{pt}\printlength{\parskip},  parskip \newline
    \uselengthunit{pt}\printlength{\ParSkipAmount}, ParSkipAmount.  \newline
    Why is it that if I set ParSkipAmount equal to parskip, it becomes 0?


    \subsection{This section demonstrates the spacing I want}
        First paragraph.

        I like the list to appear right below text (via topsep)
        \examplelist
        And the next part to be a new paragraph (via after).
    \subsection{See how the spacing below this header and the following list is the same as the space for the previous section's header and ''First Paragraph''? It was smaller if I did not use before=hfill... why?}
        \examplelist
    \subsection{And also see how the space above this header is larger than that of the space before the previous section header? How do I get rid of the vspace on the after if there is a following section/subsection (by using setlist or patching)?}


\end{document}