Another advantage from having a UniFi switch is if you are away from a site it's really easy to reboot devices connected via PoE if they crash from the UniFi app on your mobile. You get the notification that an AP is not responding and can just click the port and reboot in seconds.
Honestly, not a feature I would imagine you using much unless something is horribly wrong, I ran Unifi AP's for something like a decade, if they went down properly and the normal controller reboot option wasn't working, it usually ended in a reset button job rather than a forced reboot. As you don't rush to update firmware, that's not going to be that often. Also in this example of someone calling from home, just asking them to remove the cable from the port marked LOUNGE AP and put it back in would have the same effect. I suppose I could enable Aruba's cloud management, but it's literally never been an issue up till now and I much prefer on-prem now.
Just on these two aswell. I still might go the much cheaper camera route like Eufy etc. However being hard wired makes far more sense. I think as long as i can add in facial recognition and some of the features like that. The main shortfall sounds like it's around integration with Google Home etc without workarounds with Home Assistant etc. Either way it's nice to have as an option at least.
The Ultra seems like a decent switch but too small really, and i'd prefer to avoid having multiple switches, when i could just have a single 24port one.
Understood, depending on the number of cameras etc. you might get away with the 16, but it's only 8 PoE ports and you already are looking at 2-3 AP's, the Standard 24 PoE at least gives you 16 PoE+ ports (90w) and 8 standard ports, if you feel like you'll get the added value from that then far better to spend the extra and have no regrets. I just couldn't reconcile paying that much of a premium for half the PoE capacity on 2/3 of the ports and no 10Gb links, but those aren't your priorities and I get that, and in the end picked up a used version for £90 vs £360ish - the savings paid for a U6 Pro and G4 Doorbell.
Camera wise you have a number of other options from conventional NVR's to software NVR's such as Blue Iris or Frigate + Coral TPU or Unif Protect. Protect is simple and the SE has it built in, but the camera's are the weak link. Hikvision and Dahua make solid built quality cameras that stand up to UK weather and decent sensors that produce very usable low light/dark images in full colour for reasonable money, it doesn't always follow that more megapixels are better, but the bigger sensors do tend to allow for identification/recognition from further away. Unifi produce OK build quality camera's that have a habit of turning yellow and produce reasonable B&W night time visuals as far as the IR will stretch. With other cheaper camera's the spec sheets often don't tell the full story, if it did, we'd all be fitting Reolink camera's because they're cheap and on paper look decent. You can trick Protect into working with third party camera's, but i'd be wary of bodging my security system if it was actually important. Anyway, probably better dealt with in the CCTV thread.