I would like an alt-homepage where the slider uses the pages instead of the posts.
You need to edit the alt-homepage file inside the theme folder, then check for this line of code and add this, we are going insert this argument, 'post_type' => 'page', so the result will be:
$args = array(
'post_type' => 'page',
'posts_per_page' => 10,
'post_status' => 'publish',
'post__in' => get_option("sticky_posts")