I've been doing research only on the landing page for 2 days. I made a lot of notes. Let me tell you 2 of the best methods I've learned.
Long landing pages are more advantageous than short landing pages. Because the more he/she knows about you, the more he/she trusts you.
Users do not read, they scan with their eyes.
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My only suggestion is that the only way to know for sure is to test. A/B testing will tell you exactly what works. If you are not A/B testing your landing page, you are simply wasting money.