Homepage Headline Spacing

@Michael: You can change the margin top as per you need in the following css and then add it in “Appearance => Theme Options => Custom CSS” box.

#homepage-message {
    margin-top: 50px;
}

I don’t recommend you to change the header right font and size as for this you need to change to all responsive layout as well. So, it might be problematic for your mobile devices.

Yes, you can change colors and border as following.

#secondary .widget { 
    border: 1px solid #e6e6e6;
    color: #404040; 
}
#secondary .widget .widget-title {
    color: #222;
}
#secondary .widget a {
    color: #757575;
}