

I did a very similar setup very recently. Its not bad. I did try piefed first as some people suggested, but had some issues and it felt like it just wasn’t ready yet. I switched to self hosting lemmy and really like it. I also went with Brevo for email (I started with sendgrid, would not recommend).
Main difference for me is I am using cloudflare (they are my registrar and they allow me to deal with the CGNAT at no extra cost which you don’t have to deal with not to mention a pretty solid WAF for free tier). You may want to implement a WAF of some kind to keep the federation in check. I federate both lemmy and a matrix home server and it doesn’t eat up too much bandwidth.
I also like saving money, so a VPS is something I was trying to avoid. Personally, I don’t think the VPS does a much for securing your home network as people are trying to say here. It is another layer of security, but it’s not a panacea. Not saying I’ll never try it though.
I run a self hosted server for my household and my family gets a lot out of it. I’m not quite sure I’d consider it a gift as much as I do a way to save money and have more privacy and control. To be more blunt, I do not expect my wife would feel happy with me telling her it is a “gift” for her as it is clearly a hobby of mine.
For your question on OS, truenas scale has worked really well for me. If you have comfort running Debian server, that’s a great way to go as well. I think truenas scale would fit you well for one of your specific notes, “Having a simple container interface for future features like homeassistant and jellyfin et al is great too.” I love how easy my containers are to work on and maintain in truenas.
Ultimately, I think you should spin up every OS you are considering and look around first. It would only take a few hours of your time and it’s a very personal choice to a certain degree.