More frequent manual updates are a great idea, but there are some considerations to be thought through if you decide to automate this.
Primarily, you'll need to consider i18n. Presumably the news feed is available only in English? If so, will we still be able to offer translated versions of the feed and how do you think that could be managed? Some languages are actively translating the news feed (Template:MediaWiki News/fr for example) so thought should be given to how this would work if the feed was automated. Also, and regardless of whether it is manual or automatic, we need to consider what impact a large increase in frequency will have on the translating process. If the translations can't keep up and things are too often out-of-sync, it may be better for non-English pages to have a current feed in English than an out-of-date feed in the correct language, but this is something that should be discussed with the users of those other languages. I would recommend contacting any active translators to gauge their opinion beforehand.
Also, consideration should be given to what happens to the old content of that template (which shouldn't simply be lost, imho), and in particular the impact it will have on News which also transcludes it (as well as other, less prominent transclusions, such as Developer hub/ru). If you're updating it manually, you should be moving old news into the 'Older news' section once you no-longer want it on the home-page, but how will it work if this is a live feed?
Just some things to consider before diving in - I am all for improving the timeliness and variety of our news feed!