Team Brainstorm Force:

You can remove those three dots using our filter hook. You just need to add the following function to your child theme’s functions.php 

/*
 * Remove helip from read more link
*/
function remove_helip_from_read_more( $output, $output_filter ) {

	$output = str_replace( '…', '', $output );
	return $output;
}

add_filter( 'astra_post_link', 'remove_helip_from_read_more', 10, 2 );

You have to use either astra_post_link or astra_the_content_more_link hook depending where you want to remove ellipsis.

Instead of using child theme's function.php you can use code snippet WordPress plugin, for example Code Snippets.

You can make Astra theme content 1920 px width or stretch it to full width, but what is you want to make it stretch full width but with same content margins as with other layout options? Here's how:

1. Customize → Global → Container → Layout: Full Width / Stretched
2. Add custom CSS:

.ast-page-builder-template .site-content>.ast-container {
   margin-right: 35px;
   margin-left: 35px;
}

.single.ast-page-builder-template .entry-header {
   padding-left: 0;
   padding-bottom: 0;
   max-width: none;
}

.ast-page-builder-template .comments-area {
   padding-right: 0;
   padding-left: 0;
   max-width: none;
}

.ast-page-builder-template .site-content #primary {
   margin: 4em 0;
   padding-right: 60px;
}

.ast-page-builder-template .ast-archive-description,
.ast-page-builder-template .entry-header {
   margin-top: 0;
}

.ast-page-builder-template .ast-archive-description,
.ast-page-builder-template .entry-header {
   padding-left: 0px;
}

You can add custom CSS for example either in Customize → Additional CSS or with CSS Hero plugin. (I'm a happy user of CSS Hero plugin and the link is an affiliate link.)