Landing pages need to have one purpose - to achieve the highest possible conversion.
The overall purpose of the WSO is to collect data to improve your landing pages. To collect data, it is good to be experimental and test on some graphic elements which the customer may not use on their existing website.
The best final results are achieved by making 3-4 iterations with a few weeks interval rather than making completely "perfect" experiments down to the smallest detail. WSO does not optimise one landing page - it is the redesigned landing page that is optimised.
The landing page needs to have one purpose to achieve the highest possible conversion. Keep the focus by avoiding disturbance or additional offers. The landing page exists to get the customer to make a call to action on one particular offer.
A good model to start with is AIDA. With this model in mind Guava consider the customer's situation and optimise on the keywords that appear on the customer's Adwords, in the text of the Adwords and linked to the landing page.