Zones, frames, whatever it is called. The less you have them in your screen the better. Bloomberg TV made it famous, until they realized that the more information you cram into your screen, the less you actual absorb. Then some websites developers or owners decided that they will also try to cram even more frames to put their or customer banners in each frame. This is acceptable due to the face when you are visiting a website, you are practically less than 10 inches away from the computer  screen. Sadly, some digital signage network operators decided to do the same with their screens. They thought that since their screens are usually 40" or above, they can even have more frames and sell ads in each frame. I once saw screens in a  shopping mall that had no less than 6 frames. Needless to say, the company that owned the network closed down. The first thing that you should remember, that in most cases digital signage networks is mostly outside the home, hence some call it Out of Home TV. But unlike your home TV which when you sit in front of it, you actually sit to watch. But hardly anyone that goes to the mall to watch advertisement on the screens. They are too busy walking and shopping.  So the bigger the message the more likely it is going to be noticed. And you cannot have the  message big when you have divided your screen into 3 frames or more. Advertisers usually do not like when their ad is shared with news ticker that tells them that a bomb in Afghanistan has killed more than 20 children. Fortunately, software like Scala allows any content to gracefully appear full screen without any glitch and once shown, your screen channel can go back to your multiple frames layout.

So here is my advice:

• Avoid frames, 2 is fine, 3 is a bit to much, any more is not recommended
• Make sure that the software you are using allows any message, including a TVC to appear full screen over-riding any other frame in the screen. Make sure that it is done gracefully
• If you are going to have a news ticker, make sure  your font size is no less than 60
• The less words you put the more people would notice. If you try to copy the content of a website, give the URL instead.
• IF you have few words to show, try to make an art of it. Do not just use simple text.