If you don't like backstretch, you might prefer to display a normal image instead. Once you've removed the enqueue scripts functions from front-page.php, all you need to do is output the background image by hooking it after the header.

delete-backstretch-stuff.php

<?php

//* Enqueue scripts
add_action( 'wp_enqueue_scripts', 'minimum_front_page_enqueue_scripts' );
function minimum_front_page_enqueue_scripts() {
  
	//* Load scripts only if custom background is being used
	if ( ! get_background_image() )
		return;

	//* Enqueue Backstretch scripts
	wp_enqueue_script( 'minimum-backstretch', get_bloginfo( 'stylesheet_directory' ) . '/js/backstretch.js', array( 'jquery' ), '1.0.0' );
	wp_enqueue_script( 'minimum-backstretch-set', get_bloginfo('stylesheet_directory').'/js/backstretch-set.js' , array( 'jquery', 'minimum-backstretch' ), '1.0.0' );
	wp_localize_script( 'minimum-backstretch-set', 'BackStretchImg', array( 'src' => get_background_image() ) );
	
	//* Add custom body class
	add_filter( 'body_class', 'minimum_add_body_class' );

}

//* Minimum custom body class
function minimum_add_body_class( $classes ) {
	$classes[] = 'minimum';
		return $classes;
}

minimum-no-backstretch-front-page.php

<?php

//* Add widget support for homepage if widgets are being used
add_action( 'genesis_meta', 'minimum_front_page_genesis_meta' );
function minimum_front_page_genesis_meta() {

	//* Remove entry meta in entry footer and Genesis loop
	remove_action( 'genesis_loop', 'genesis_do_loop' );

	//* Add Genesis grid loop
	add_action( 'genesis_loop', 'minimum_grid_loop_helper' );

	add_action( 'genesis_after_header', 'minimum_home_image', 9 );

	//* Remove entry footer functions
	remove_action( 'genesis_entry_footer', 'genesis_entry_footer_markup_open', 5 );
	remove_action( 'genesis_entry_footer', 'genesis_post_meta' );
	remove_action( 'genesis_entry_footer', 'genesis_entry_footer_markup_close', 15 );

	//* Force full width content layout
	add_filter( 'genesis_pre_get_option_site_layout', '__genesis_return_full_width_content' );

	if ( is_active_sidebar( 'home-featured-1' ) || is_active_sidebar( 'home-featured-2' ) || is_active_sidebar( 'home-featured-3' ) || is_active_sidebar( 'home-featured-4' ) ) {

		//* Add Home featured Widget areas
		add_action( 'genesis_before_content_sidebar_wrap', 'minimum_home_featured', 15 );

	}
}

function minimum_home_image() {
	//* Do nothing if we have no background image.
	if ( ! get_background_image() ) {
		return;
	}

	//* Display the background image.
	echo '<img class="custom-bg" src="' . get_background_image() . '" title="' . get_bloginfo( 'name' ) . '" alt="' . get_bloginfo( 'name' ) . '" />';
}

//* Add markup for homepage widgets
function minimum_home_featured() {

	printf( '<div %s>', genesis_attr( 'home-featured' ) );
	genesis_structural_wrap( 'home-featured' );

		genesis_widget_area( 'home-featured-1', array(
			'before'=> '<div class="home-featured-1 widget-area">',
			'after'	=> '</div>',
		) );

		genesis_widget_area( 'home-featured-2', array(
			'before'=> '<div class="home-featured-2 widget-area">',
			'after'	=> '</div>',
		) );

		genesis_widget_area( 'home-featured-3', array(
			'before'=> '<div class="home-featured-3 widget-area">',
			'after'	=> '</div>',
		) );

		genesis_widget_area( 'home-featured-4', array(
			'before'=> '<div class="home-featured-4 widget-area">',
			'after'	=> '</div>',
		) );

	genesis_structural_wrap( 'home-featured', 'close' );
	echo '</div>'; //* end .home-featured

}

//* Genesis grid loop
function minimum_grid_loop_helper() {

	if ( function_exists( 'genesis_grid_loop' ) ) {
		genesis_grid_loop( array(
			'features'              => 0,
			'feature_image_size'    => 0,
			'feature_content_limit' => 0,
			'grid_image_size'       => 0,
			'grid_content_limit'    => 250,
			'more'                  => __( '[Read more]', 'minimum' ),
		) );
	} else {

		genesis_standard_loop();

	}

}

//* Run the Genesis loop
genesis();

minimum-pro-custom-home-image.css

.home .custom-bg {
	display: block;
	margin: 60px auto 0;
	margin: 6rem auto 0;
}

.home .site-tagline {
	margin-top: 0;
}

/*
Add this rule within the already existing @media only screen and (max-width: 1023px)
You only need to add the .home .custom-bg rule. The rest is just to illustrate how the rule
should be placed in the existing media query.
---------------------------------------------------------------------------------------------------- */
@media only screen and (max-width: 1023px) {

	.home .custom-bg {
		margin: 0 auto;
	}
}