I use terminal Vim on Cygwin Mintty with both using solarized scheme on Windows. I've got the same problem and found a workaround which is not perfect but might be suitable for you.
My goal was to copy syntax highlighted code to E-Mails and documents. For this to achieve, I don't have to generate HTML. I configured Mintty terminal to copy rich text:
- Right-Click the title
- Select 'Copy as rich text'
As I use the solarized dark scheme in Vim, I paste the content to other applications and remove the background color there. The result looks fine:
VIM with solarized dark scheme:
Pasted to MS Word with background color removed manually:
Unfortunately, with this solution, you lose the ability to Vim-select the text. This brings problems with splits and line numbers. But you can close all splits and remove the line numbers using