https://store.steampowered.com
1. I think this is an effective example because it is easily readable, is customizable, and informative.
2. The intended goal is to advertise and possibly sell games. So it shows off the current best deals, scrolls through the newest popular releases, and shows off some of the top sellers. All of this while not drowning the user in information
3. It uses images, screenshots, and labels to tell a story. The most important information being the price, any discount, and the general feel of the game.
4. This example can easily be adapted to mobile or social because it is a vision based advertisement instead of a text based one. So, it requires less space and makes an immediate impact.
5. I would not add more information, but instead widen the current information to take up more of the screen, up to 10% more to not overwhelm the user. I think doing so will make the pictures more noticeable and therefore effective.