There is a related issue: Character font/display, but on the opposite, I would prefer all Chinese characters to be written in HeiTi-style fontface, i.e. San-Serif (instead of current KaiTi) everywhere except the drawing area.
The reason is that the wast majority of Chinese that I read is written in HeiTi-style. And when I learn the words only in KaiTi, I just have troubles later recognising the same characters in HeiTi. Compare for example the word 咖啡: in sans-serif 口 radicals are stretched and the word looks much more dense.
This is probably not the best example, but I just wanted to show the significant visual difference, which is even more noticeable when reading a text and needing to think how the character is spelled to remember that you actually know it.
I suppose some people won’t agree with me, so it would be nice to have a setting where user can choose preferred typeface.
P.S. There is a wonderful sans-serif open source font with the full CJK characters set: Source Han Sans.