Before I really get into what you’re asking about, how many family members are we talking about? If it’s just a few, consider whether Tailscale might meet your needs–that would allow your family members to access these resources without exposing services to the whole Internet, and thus would be considerably more secure. See:
and
Please don’t confuse Nginx Proxy Manager (NPM) with Nginx–the former does indeed have an app available and provides a relatively straightforward GUI to configure it; neither of these is true of the latter. There’s a guide for NPM here:
One of its drawbacks is that its logging is limited at best, making it difficult to debug when things (like issuing a certificate, for example) don’t work as expected.
I have some experience with Caddy and wouldn’t describe it that way, but it’s much more able to “do the right thing” out of the box than other web servers/RPs and thus needs much less (and much simpler) configuration.
Traefik is a very popular reverse proxy, of course. One of its more helpful features is that you can configure a proxy destination via labels in your Compose file, so you don’t directly need to edit Traefik’s configuration. Caddy can also be used this way, but it isn’t as common or well-documented. Traefik’s initial setup is probably the most complex, but it’s probably the easiest in day-to-day operation, particularly if you’re adding or removing apps.
So: Consider using Tailscale to avoid needing to open up your services to the Internet at all. Then, the RP recommendation would depend on how you’re going to be running your apps. If you’re doing everything via the “custom app” or pure Compose route (which is what I’m doing–installed Dockge from what they’re now calling the App Store, and then deal with the Compose files directly), I’d recommend (and am using) Traefik. All regular TrueNAS apps? NPM. Caddy if you want to prepare the config file yourself, as it’s the easiest to do this.