Can we change the color of the > arrows?

You can change the color of the grey arrows by adding this to your style.css:

.wp-post-navigation div a:after {
    color: #xxxxxx !important;
}

Just be sure to put your color hex code in place of xxxxxx ??

Alternately, you can make the arrows disappear by adding this instead:

.wp-post-navigation div a:after {
    display: none !important;
}