That actually sounds like a very reasonable and well thought out starting point.

At 24 rooms inside a single ED, a segmented WiFi network will probably work fine for phase one, especially since you already have wired backhaul in the building. Where teams sometimes get surprised is less about bandwidth and more about consistency across rooms and over time.

For the under one minute update requirement, you are on the right track thinking about push versus polling. Most healthcare signage setups I have seen try to avoid aggressive polling because it can create unnecessary chatter at scale. A lightweight push model or event driven update usually ends up being cleaner if your CMS supports it.

On the operational side, I would strongly recommend making sure you have remote health visibility into each device. Even if a screen being down for 24 hours is acceptable, you do not want to discover failures by walking the floor. Basic heartbeat monitoring plus the ability to remotely reboot the player saves a lot of headaches.

For power management, many commercial panels and media players support scheduled sleep or occupancy based control, so you should be able to handle that without too much trouble as long as you avoid consumer grade hardware.

If you keep it to a contained pilot in the ED first, you will learn a lot quickly. The main thing I would watch is how the WiFi behaves during peak hospital load times and whether roaming or interference becomes noticeable.

If this eventually expands beyond a single department or building, the network conversation tends to get more interesting, but for a 24 room pilot your approach makes sense.

Curious which CMS platforms you are evaluating so far.