I was using PT Serif (for headings) and PT Sans (for body text) and I was satisfied... but when I saw Source Sans Pro I knew it was time for a change, but I can't find any good serif font (for headings) without ending up with an ugly, artificial etc. combination. I may be an amateur in this, but I think I know when something looks ugly. For example: in PT Serif (headings) + Source Sans Pro (body text) combination uppercase "J"s just "can't stand eachother"). I intend to use it at home and for writing some reports at work - nothing too long (there will be some tables too). Both printed and on-screen "performance" is important. Fonts with SIL Open Font License are strongly prefered (I bought MS Office and I just don't want to buy any more fonts at this time).
Source Sans Pro preview: http://www.google.com/webfonts/specimen/Source+Sans+Pro
Thanks in advance for any replies.