Removing template part when not on homepage if / else

I believe what you need is is_page().

if (is_paged()) {
  // page 2 or later of an archive
} else {
  // only the first page of an archive
}

With your code, I think but am not 100% sure, that you want:

if( !is_paged() && ( is_home() || is_front_page() ) ) :
 get_template_part( 'hero' );
else :
 get_template_part( 'blank' );
endif;