Less information focusing on one or two key benefits that you believe is/are the most important topic (s) of interest to your target audience.
Refrain from too much information which have a significant tendency to drive away potential visitors.
REMEMBER that huge majority of web surfers have less than 10 seconds to give you, to make a quick judgment of the offer in your Ad.
Mention in your short Ad the pertinent one to three most popular keywords that search engine users are targeting in their search.
REMEMBER that search engine users are the most desirable source of targeted traffic.
REMEMBER to test different ads with varying font and margin colors and keywords.
Use some software tools if you are able to use, in helping you find the best keywords for you to use. Some software will give you the highest ranking search engine URLs, to allow you to research their best keywords and methodology in attaining high rankings.