Correcting rotated molecule

Question

I use chemfig to draw cyclic molecules. Quite often, it is desirable to reorient the molecule for which I use the optional directive [rotate=-18]. Sometimes this is barely acceptable but most often just wrong.

How do I achieve the following -

1. The letters should not be rotated even if the molecule is.
2. The double bond should be rotated in its entirety.
3. The molecule should not be shifted upward or downward.

Or is there any way to achieve my objectives.

My MWE is as follows

\documentclass{scrartcl}
\usepackage{chemfig}
\begin{document}
\begin{tabular}{ccc}
    Unrotated & Rotated & \\
    \chemfig{*6(-=-=-=)} & \chemfig[][rotate=-30]{*6(-=-=-=)} & Acceptable\\
    \chemfig{*5(---O-(=[:145]O)-)} & \chemfig[][rotate=-55]{*5(---O-(=[:145]O)-)} & unacceptable \\
    \chemfig{*5(-N(-H)-=-=)} & \chemfig[][rotate=-18]{*5(-N(-H)-=-=)} & unacceptable
\end{tabular}
\end{document}

Answer 1

I have a partial answer. This takes care of my concern number 1 and 2. However the molecule is still shifted downwards probably because it is rotated w.r.t. the origin.

This time I am using a () outisde the ring and issuing a [::-30] directive just at the start of ().

Please see this MWE

\documentclass{scrartcl}

\usepackage{chemfig}

\begin{document}

\begin{tabular}{cccc}
    Unrotated & Rotated & Rotated & \\
        & rotate=-30 hack & [::-30] hack \\
    \chemfig{*6(-=-=-=)} & \chemfig[][rotate=-30]{*6(-=-=-=)} & \chemfig{([::-30]*6(-=-=-=))} & Acceptable\\
    \chemfig{*5(---O-(=[:145]O)-)} & \chemfig[][rotate=-55]{*5(---O-(=[:145]O)-)} & \chemfig{([::-55]*5(---O-(=[:90]O)-))} & unacceptable \\
    \chemfig{*5(-N(-H)-=-=)} & \chemfig[][rotate=-18]{*5(-N(-H)-=-=)} & \chemfig{([::-18]*5(-N(-H)-=-=))} & unacceptable 
\end{tabular}

\end{document}