Custom bracket and arrow symbols (jazz music notation)

Question

I am trying to create a custom command for jazz music notation, like the arrow and brackets below:

I managed to create the following custom commands

\newcommand{\bracket}{$\underbracket{\phantom{...}}_{}$}
\newcommand{\arr}{$\phantom{.}^\curvearrowright \atop \phantom{.}$}

which appear as

I am asking you for:

1-A dashed version of both the bracket and the arrow.

Secondarily, the following:

2-Ideally, bracket and arrow should have the same thickness and length, slightly longer than my example.

3-Both ends of the symbols should be located at the center of the chords, below/above the chord's name (you see that in my custom character the ends are before/after the chord name, while in the top picture the ends are correctly placed above/below the chord).

EDIT - The solution has been further improved into this other question: https://tex.stackexchange.com/a/639428/203987

Answer 1

TikZ and especially tikzmark comes to mind:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{tikzmark}
\usepackage{leadsheets}
\setchords{
  major-seven = \textsuperscript{$\Delta$} ,
  major-nine = \textsuperscript{$\Delta$9}
}

\begin{document}

\tikzmark{ii7}\writechord{Cmi7}\qquad
\tikzmark{V7}\writechord{F7}\qquad
\tikzmark{I}\writechord{Bbmaj7}
\begin{tikzpicture}[remember picture, overlay]
  \draw[->]
    ([shift={(.3em,1em)}]pic cs:V7) to[bend left]
    ([shift={(.3em,1em)}]pic cs:I) ;
  \draw
    ([shift={(.3em,-.3em)}]pic cs:ii7)
    --++ (0,-1ex) -|
    ([shift={(.3em,-.3em)}]pic cs:V7) ;
\end{tikzpicture}

\end{document}