Why would customers not be your #1 priority when creating your beta? They are all that matters!

Once you have a handful of pre-orders you'll be able to find common patterns across them - similar industry sectors, geographic locations, company size etc. which will give you a tremendous amount of data to help figure out your product/market fit.

Pour your time and energy into providing the product for the group of people who are saying they want it and putting their money where their mouth is.