I am not sure if anyone would call this "inappropriate" to do, but i would love to give it a try if it's legally alright and dueable of course.
The WP3 standard Theme TwentyTen has an additional CSS file that actually tells WordPress to style the WYSIWYG Editor's text area so you can use the exact same font attributes while adding contents as people will see on your frontend, compare that to the hard to read standard WP3 textarea font and you'll probably want that in whatever Theme you prefer to use as well - just, HOW TO HACK this around??
Just uploading the particular CSS file from the twentyten to your active Theme will do no more than sow it in your Themes Editor, but of course, it's not connected to the FUNCTIONS:PHP file of your active Theme yet.
So, the question to the coding pros would be:
What and where can i add in functions.php to get it and grab and make work the added "editor-style.css" ????
Perhaps it's possible to just copy and paste the respective portion out of the twentyten functions.php, but that looks already a bit to complicated for Mr. low-coder here, if that was the easiest solution, what section exactly would i have to copy and paste???