Welcome to the Elastic Community!
First off, I am very excited to read that you are already thinking about getting all your data in one place. That's exactly our goal at Elastic: providing you with a platform that supports all of your data needs in one place, allowing you to make sense of everything that is happening in your world from a single powerful experience.
With regards to pricing and free versions, all the details will come at GA. I can confirm that pricing for the fully-featured version of this product will be resource-based, and not based on user count or number of active connectors, for example. This aligns with how we approach pricing across all of our solutions from APM to Logging and Security. This ensures that you always get the most optimal value out of your investment. There are currently no details with regards to a free version of this product (e.g. included in Basic), but this may evolve in the future.
For the time being, make sure to download the latest beta and explore all of the product's awesome functionality. The user experience is quite a refreshing take on Enterprise Search
Let us know what you think!