I'm doing CPA with SEO traffic but have poor conversions

Hey guys, as the title says I have some sites for CPA, all traffic is from organic searches. The problem is I'm getting only about 1-3% conversions after the visitors reach the advertiser's landing page. I'm making the sites good for SEO, they are not so pretty, probably that's why the conversion ratio is so low. On the other hand, I can't make a great looking landing page without content only because visitors can like it just because I will drop in serps.
*** The offer is simple email submit ***

In that case what changes do you recommend me to do? I even added video at autoplay and explained the visitors what should do etc. but without effect....

If anyone can share a sample landing page that is getting good conversions it would be good.

Thanks in advance,
nECA

May be nobody share with you.Because I asked many time but I didn't get.