Don't try to pack in every detail and feature of your website into one advertisement. Segment it out for each landing page. Ensure it's relevant
MailChimp has a great landing page that entices and doesn't overdo it:
6. Develop your Unique Value Proposition
Notice the "Easy Email Newsletters" - in three words, you can just about tell what they're all about. Additionally, they use a chimp and what is that? Another term for monkey. And we have all hear the phrase "So easy a monkey could do it." Thereby, by create that image (in a very subtle way) in your head. Remember how I said that psychology plays a huge effect on landing pages and higher conversions. Think about that a bit.
Also, it might be a good idea to research your competition. Not to copy them in any way!
Simply to determine what they are using and how it works for them. Again, this works in keyword research, content marketing AND landing pages. Create your own unique value proposition that fits your niche.
Like you said psychology, visuals, catchy marketing, continuous monitoring and improvements to your CTAs , your keyword approach related to relevancy , ( does the way the person arrives to your site make sense based on what you are actually selling or promoting) are all very important parts of the CTA puzzle.
You only have so much time for your reader to make that decision.
So many folks out there do not even have well defined, and easily seen CTA icons.
The easier the process is to your visitor, and the more clear cut it is, the more likely he or she will move forward and make a purchase.
Thanks again for the training PJ.