Well, low contrast is also bad for the eyes, as it makes reading the text harder.
One thing I really hate is that even on current systems, the font suddenly changes from thin to thick when upping the font size. When I change it to 120% of the current size, it's all perfectly readable. But this is just the font size then where it changes from 1px thick to 2px thick (and it's actually why it looks better).
Too bad using page zoom also makes images larger, which looks very ugly.
As for "You can always edit it client side." - is there any "user friendly" way to do that? I know I can use the user style sheet feature and manually write a CSS file, but I bet I'm not the only user who has a hard time reading text at that low contrast and thin font.
Also, when I try to increase the font size to a sensible value, I get problems with the line height, as you somehow broke the line height increasing together with the font size.
EDIT: while I was writing this, I noticed that when now switching to Verdana instead of Bitstream Vera Sans, it actually looks good. Can you do that in the CSS, so everyone can get a nice readable font?
Another thing... can you now also increase the line height? When selecting text, the selection marking overlaps the previous line...