Bump the Proceed to Checkout button right next to the Update Cart button (this looks AWESOME on mobile devices!!)

move-proceed-to-checkout.php

add_action( 'woocommerce_cart_actions', 'move_proceed_button' );
function move_proceed_button( $checkout ) {
	echo '<a href="' . esc_url( WC()->cart->get_checkout_url() ) . '" class="checkout-button button alt wc-forward" >' . __( 'Proceed to Checkout', 'woocommerce' ) . '</a>';
}