Having Open Source Project on GitHub does not mean you need to become less agile. First there will not be instantly 1000 of people sending you pull requests, second even if they do - you have no obligation to take them in.
However if you say, we can write crap code... and no one would know because they only see binaries, this is not really a way gain a good confidence
In my opinion those days just having a "binary you can use" is the worst way to go for something like database/data store. If you are not sure about your Open Source plans having something like SaaS solution with free tier so users can experiment easily could be way to go
DB sales of open source are based on cloud and security. You can keep some security as open core along with cloud deployment.
Open source is about expanding the total potential market even if you only capture a portion of the value there.
We are a small team of developers, and currently EloqKV is still under heavy development. We would like to maintain agility and quickly iterate and improve our product with consistency with our customer's feedback. However, we are actively evaluating multiple paths to open sourcing our technology and any suggestions and concerns will certainly be kept in our mind as we progress.