Granted, most of the communication on social media is done through writing. It is however important that you acknowledge the very important role that images are playing on social media today. It is also important that you acknowledge the fact that there are different types of people in the world; there are those who are audio and like listening but there are those that are visual and like to see images so as to understand the point that is being put across. For you to get those free likes that you are looking or on social media, you have to be able to appeal to all people across the board.
This does not go to say that you should alter all your content and make it visual; this will then mean that you have locked out those who prefer written content. You need to analyze your audience and find a middle ground. You can also choose to look at it from the point of the content that you will be posting and the message that it is intended to send. Will the message be better passed in writing or as an image? All in all, try and find a good blend of words and images to post your content with to get those free likes.