parskip and title spacing conflict

Question

Issue

I am trying to set spacing between paragraphs using \parskip but it also affects section titles and "breaks" formatting.

Question

How can I set up a skip between paragraphs without having it influence section formating?

Bonus question

The frame around the title in the screenshot without parksip is closer to the top than to the bottom of the text. Why is that and how can I fix it?

Demo

1. Default

2. With parskip

MWE

\documentclass{article}
\usepackage{mwe}
\usepackage{titlesec}
\setlength{\parskip}{1em}
\titlespacing*{\section}{0pt}{0pt}{0pt}
\titleformat{\section}
  [frame]
  {\normalfont}
  {}
  {0pt}
  {\quad \Large \bfseries \Roman{section}. \enskip \MakeUppercase}
\begin{document}
\section{Section 1}\label{sec:section-1}
\lipsum[1]
\subsection{Subsection}\label{sec:subsection}
\lipsum[2]
\lipsum[3]
\end{document}

Relevant thread

Answer 1

Proposed solution

Following the advice of @DavidCarlisle, I removed the custom settings on parskip and simply let the parskip package manage the basic spacing.

Since I still wanted to customize some things, I used the following settings using the titlesec package to tailor it to my needs:

\titlespacing*{\section}      {0em}{.75em}{.5em}
\titlespacing*{\subsection}   {0em}{.50em}{.25em}
\titlespacing*{\subsubsection}{0em}{.50em}{.25em}
\titlespacing*{\paragraph}    {0em}{.25em}{.25em}

MWE

\documentclass{article}
\usepackage{mwe}
\usepackage{titlesec}
\usepackage{parskip}
\titlespacing*{\section}      {0em}{.75em}{.5em}
\titlespacing*{\subsection}   {0em}{.50em}{.25em}
\titlespacing*{\subsubsection}{0em}{.50em}{.25em}
\titlespacing*{\paragraph}    {0em}{.25em}{.25em}
\titleformat{\section}
  [frame]
  {\normalfont}
  {}
  {0pt}
  {\quad \Large \bfseries \Roman{section}. \enskip \MakeUppercase}
\begin{document}
\section{Section 1}\label{sec:section-1}
\lipsum[1]
\subsection{Subsection}\label{sec:subsection}
\lipsum[2]
\lipsum[3]
\end{document}

Demo