I'd contest that this is everything that you need to know. Or perhaps more accurately, everything I need to know.
It's certainly not intended to be exhaustive and I am definitely not a network engineer but I think you could operate at a reasonable scale within a single well laid out VPC. Of course there'll be a point for peering etc. but you might not need that.
Network ACLs have been pointed out as missing from this before but quite a few people said that they were right not be included. I didn't put them in because I've never used them so didn't fall under 'need to know' from my perspective.
IPv6 is another point of contention but again it's not something I've ever used and so, apart from any other controversies with it ("...IPv6 which is only marginally better than IPv4 and which offers no tangible benefit...", https://varnish-cache.org/docs/trunk/phk/http20.html), I'm not qualified to write about it.
EIPs and ENI should probably have been in there but I don't tend to use those that often either so they didn't occur to me.
I'm not sure that VPC Gateways, DNS or DHCP are necessarily need to know things either. VPC Gateways are for a specific routing optimisation which not everyone is going to need. I didn't know the details of the DNS set up for a VPC so thank you for that.
Thank you for the feedback - I really appreciate you taking the time.