Indeed Coming Soon ultimate Responsive for WordPress with 2 modern layouts and Countdowns is the most all in one desired and use Plugin on his niche.
Indeed Coming Soon let you continue your work on website while your visitors see the Coming Soon page. When you finish your website just bring it live using One Button!
You decide which Users can see the Website or not based on their WP Roles. If only part of the website needs to be restricted with the “Coming Soon” page now you can set which pages are available for your visitor and which not.