Whilst the design of your landing page is important, the actual organisational layout is key to creating a page that converts well. That is, the visitor takes the action that you want them to.
You need to make sure that you emphasise the right message and actions, but take care not to over do it. Elements that are too large and obvious can often be ignored by visitors. This is known as banner blindness. The visitor sees the message as an advert and ignores it.