Great point about the ease of deployment @seewhy and I agree that balancing out of the box ease of use with high level of flexibility is really key. Interestingly though, our experience is not necessarily that people have problems installing and running central (though some noobs do find it daunting). This tends to be because local IT teams are awesome and helpful. A lot of the problems come from the need for data sharing agreements, contracts and trans-national data law, which can make things really tough to do in an emergency. Unfortunately that's some pretty over our heads stuff that we can't really do much about for one another and just have to suffer with alone!
The whole 'out of the box' thing extends in my thinking beyond the installation of central and set up of devices. What there's a lot of opportunity for in case studies like those above is generalisable out of the box solutions for specific tasks. For instance, my team recently wrote a set of ODK forms and protocols for an ebola vaccine trial that we are now remixing for COVID-19 work. The forms and protocols are shareable to others doing similar trials and we're trying to put together a general use package that includes analysis and reporting pipelines along with data collection stuff (read all about it here)
We'd also love to do something similar with the emergency medical service patient information system described above as this has essentially unlimited re-use value in similar participant/patient management contexts. I kind of start to hope that something our community could look towards doing better is the sharing and co-development of some of these OOB solutions, along with documentation and protocols for use in the field.
The Excel spreadsheetiness of ODK's form design wins the hearts of many in terms of using something familiar to code up the survey/database, but when faced with a more complex data management problem, having some 'templates' could be an interesting starter solution for many newcomers.