It would be cool that a newsletter with the newest software was available. It would be easier than to periodically check flathub for new software.
This newsletter could be sent weekly, for example.
Another feature that it could have, although not as useful and more complex to implement, would be to receive alerts when a certain software a person is interested, is available. For example, instead of receiving a newsletter about all new software, one would only receive about one specific piece of software of interest. This could be done by receiving an email alert when the list of software available matches a keyword. For example: setting “Google Chrome” as a keyword, would send an e-mail when it’s available in flathub.