According to Wikipedia
Nextcloud is a suite of client-server software for creating and using file hosting services.
Summary of your evaluation
Nextcloud is perhaps the most fully featured software package for file hosting & modification. Often compared to services such as dropbox and google drive, it serves as a great general-purpose tool for file & information management. The scope of what the software can do has increased along with its maturity which has expanded its use beyond simple file storage & management.
Nextcloud's base functionality, when integrated with OnlyOffice can be compared to that of Google Drive or Office365. However, it has a growing addon ecosystem that includes the following:
- calendars (CalDAV)
- contacts (CardDAV)
- streaming media (Ampache)
- browser-based text editor
- bookmarking service
- URL shortening suite
- RSS feed reader
- document viewer tools from within Nextcloud
- connection to Dropbox, Google Drive and Amazon S3
- Web analytics (Use of Matomo (software))
- Integration of Content management systems e.g. Pico CMS
- Viewer for Weather forecasting
- Viewer for DICOM
- Viewer for Maps
- Managing of Cooking recipes
Pros and cons
- Best open-source tool on market for file management & editing
- Already containerized, hosting is reasonably simple
- Could be useful for more structured open-source organizations
- Useful for non-technical users to contribute to open-source projects & organizations
- Scope of the software is ever-increasing may conflict with other SA-Open services (like video conferencing with BBB)
- Supporting file hosting can be expensive depending on amount allotted.
Indications of maturity level
NextCloud is supported by Nextcloud GmbH and sees fairly regular updates and support. I've seen it used in a number of organizations where it was a critical service.