'proper' clickable hyperlinks with biblatex, natbib and hyperref -- (Author, Year) style

Question

Based on some experimenting and some reading (here on http://tex.stackexchange.com) I might have solved first issue I had. I have kept a strikeout-version of the first issue so that people have a change to correct me if my solution is faulty (see update from 2013-11-04 16:25:35Z below). Please feel free to let me know if the striked out text is utterly confusing to read.

I am using the biblatex package–with natbib capabilities–and the hyperref package, using the (Author, Year) style citations, and pdflatex as the engine.

I have run into two one issues.

First, \citeyear{} and the custom-made command \citejournal{}, thanks to Gonzalo Medina's answer (with the help of Audrey), do not produce clickable hyperlinks (see screenshot below this ¶).

It kinda makes sense to my why \citejournal{} does not work, but I do not understand why \citeyear{} doesn't work. According to the reference manual for the biblatex package (p. 88 [PDF link!]) "[t]he text commands (\citeauthor, \citeyear, etc.) are […] supported." Also, the hyperref should work, as long as the transformations of citations into clickable hyperlinks is support by the selected citation style (p. 47 in the reference manual for the biblatex package [PDF link!]).

I got the \citetitle{} and \citeauthor{} working with the help of this (\citetitle{}) and this (\citeauthor{}) answer, both by Audrey. I tried reproducing Audrey's method for \citeyear{} and \citejournal{}, but I got stuck.

Can anyone show me how I get the \citeyear{} and maybe the custom-made command \citejournal{} to create a link to the biography? (see below for reproducible example).

Furthermore, the second issue, from this beautiful example from Audrey I realized that it is possible to fix the links to include the postnote and bracket so that it is not only the year that is clickable but the whole parenthesis. I've tried reproducing his example, but I cannot get this to work with biblatex. Any suggestions to how I can expand the clickable hyperlinks?

\documentclass[11pt]{article}
\usepackage[utf8]{inputenc}

\usepackage[backend=bibtex,
style=authoryear, natbib=true, 
        ]{biblatex}

\usepackage{hyperref}
\hypersetup{pdfborderstyle={/S/U/W 1}}

% thanks to https://tex.stackexchange.com/a/26684/22939
\DeclareCiteCommand{\citejournal}
  {\usebibmacro{prenote}}
  {\usebibmacro{citeindex}%
    \usebibmacro{journal}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand{\citebooktitle}
  {\usebibmacro{prenote}}
  {\usebibmacro{citeindex}%
    \usebibmacro{booktitle}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand{\citeintitle}% Based on \citetitle from biblatex.def
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexfield{indextitle}}
     {}%
   \iffieldundef{journaltitle}
     {\iffieldundef{booktitle}
        {\iffieldundef{maintitle}
          {\printfield[citetitle]{labeltitle}}% Behave like \citetitle if no "main" title
          {\printtext[maintitle]{\printfield[titlecase]{maintitle}}}}
        {\printtext[booktitle]{\printfield[titlecase]{booktitle}}}}
     {\printtext[journaltitle]{\printfield[titlecase]{journaltitle}}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}


%  Thanks to [Audrey](https://tex.stackexchange.com/a/108349/22939)
\DeclareCiteCommand{\citetitle}
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexfield{indextitle}}
     {}%
   \printtext[bibhyperref]{\printfield[citetitle]{labeltitle}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}


%  Thanks to [Audrey](https://tex.stackexchange.com/a/75916/22939)
  \DeclareCiteCommand{\citeauthor}
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexnames{labelname}}
     {}%
   \printtext[bibhyperref]{\printnames{labelname}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}


\begin{filecontents}{bibfile.bib}
@article{einstein,
  author =       "Albert Einstein",
  title =        "{Zur Elektrodynamik bewegter K{\"o}rper}. ({German})
                 [{On} the electrodynamics of moving bodies]",
  journal =      "Annalen der Physik",
  volume =       "322",
  number =       "10",
  pages =        "891--921",
  year =         "1905",
  DOI =          "http://dx.doi.org/10.1002/andp.19053221004"
}

@book{latexcompanion,
    author    = "Michel Goossens and Frank Mittelbach and Alexander Samarin",
    title     = "The \LaTeX\ Companion",
    year      = "1993",
    publisher = "Addison-Wesley",
    address   = "Reading, Massachusetts"
}
\end{filecontents}


\addbibresource{bibfile}

\begin{document}

\noindent
cite: \cite{einstein}, \cite{latexcompanion} \\
citet: \citet{einstein}, \citet[see][p. 20]{einstein} \\
multi citet: \citet{latexcompanion,einstein} \\
citep: \citep{einstein}, \citep[see][p. 20]{latexcompanion} \\
multi citep: \citep{latexcompanion,einstein} \\
citetext, citealp: \citetext{see \citealp{latexcompanion}, or even better \citealp{einstein}} \\
citeauthor: \citeauthor{einstein}, \citeauthor{latexcompanion} \\
citeyear: \citeyear{einstein}, \citeyear{latexcompanion} \\
citetitle: \citetitle{einstein} and \citetitle{latexcompanion} \\
citejournal: \citejournal{einstein}\\

\medskip

\printbibliography

\end{document}

Update 2013-11-04 16:07:35Z

I have written this update to \DeclareCiteCommand{\citejournal}

\DeclareCiteCommand{\citejournal}
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexfield{journal}}
     {}%
   \printtext[bibhyperref]{\printfield[journal]{journaltitle}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}  

I've not updated the initial code I posted as I don't full understand––to say the least––what I am doing, but the above code seem to work.

Update 2013-11-04 16:25:35Z

Encouraged by moewe's comments I have reproduced the \DeclareCiteCommand{\citejournal} for the \DeclareCiteCommand{\citeyear}. As follows,

\DeclareCiteCommand{\citeyear}
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexfield{year}}
     {}%
   \printtext[bibhyperref]{\printfield[journal]{year}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}  

Again, I have not updated the initial code I posted as I don't really understand what I am doing yet, but the above code seem to work.