Hi,

1. Reduce pics? Do you mean image quality or size? Please install the Smush plugin: https://wordpress.org/plugins/wp-smushit/

2. Please go to Appearance > Customize > Custom CSS, then add the following code:

.side-newsfeed li {
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid #7a7a7a;
}
.side-newsfeed li:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}