I use Bitstream Charter for my document, but I'm not satisfied with the appearance of round parentheses. I'd like to replace them with the parentheses from Palatino, both in text and math mode. In math mode I managed to change the symbol font to CM with the instructions from here and here, but now the parentheses do not automatically scale with \left( and \right). A manual adjustment with \big, \Big, etc also does not work. The parentheses always stay the normal (text) size as shown below.
The example code
\documentclass{memoir}
\usepackage[T1]{fontenc}
\usepackage[utf8x]{inputenc}
\usepackage[charter]{mathdesign}
\DeclareFontFamily{T1}{alt}{\hyphenchar\font=-1}
\DeclareFontShape{T1}{alt}{m}{n}{
<5> <6> <7> <8> <9> <10> gen * alt
<10.95> alt10 <12> <14.4> <17.28> <20.74> <24.88> alt12
}{}
\DeclareSymbolFont{alt}{U}{alt}{m}{n}
\DeclareMathDelimiter{(}{\mathopen}{alt}{`(}{alt}{`(}
\DeclareMathDelimiter{)}{\mathclose}{alt}{`)}{alt}{`)}
\begin{document}
Inserting eq.~(2b) into eq.~(1) yields
\begin{equation}
A = B \left( \frac{A-\phi}{c \left(1+E^{1/m} \right)} + \frac{1}{2} \right)
\end{equation}
\end{document}
produces

My principal question is how to make the parentheses expandable. Less importantly, I'd also like to know how to change them to a font other than CM (since the CM symbols are a bit too light in comparison to Charter) and how to substitute them also in text mode (in the above example you can see that they are still in Charter).
NEXTCHARfeatures in the tfm file and alsoTOP,REP,MIDDLEandBOTTOMfor the larger composite versions. – egreg Nov 27 '13 at 18:35