I sent about a hundred emails about my product to my mailing list. I want to know what I should do next. Should be split testing the landing pages or should I be waiting for an early adopter to give me feedback?

I still have another 900 or so emails to blast to. I'm just not sure what I should be optimizing here or what I should be aiming towards.

Like the questions I want to know about the user, did they or did they not like what was on the landing page? Did the price not make sense? Why did they stop engaging? etc.