Highlights : Leaves me cold. Not needed.
History : Nice presentation but how about improve the sidebar history that already exists instead of bolting on yet more feature creep? Folks would probably happily use the sidebar more if it was refined… just sayin’
It would be amazing if the background follow the same pattern of Firefox themes. I loved <3
Great suggestion! I’ve filed a bug to add theme backgrounds to the activity stream page:
Well… if we make just a theme with dark background and white font? 
I can not stress enough how frustrated I would feel seeing Yahoo News articles every time I open Firefox. PLEASE, keep this an optional feature, because as the OP said, this is just more unnecessary feature creep that no one really needs. They can use Yahoo as their home page if they are into that kind of stuff.