While I can understand concerns about factory conditions for egg layers, is there anyone who believes there are ethical issues around eggs produced in the decidedly non-factory conditions of my backyard? I've been somewhat amazed by just how easy it has been to raise them so far and would advocate anyone who wants to enjoy eggs should give it a go.
Regarding milk: Yes, I'm in agreement, for most adult humans the soy / almond / oat / etc options are perfectly good, apart perhaps from baking.
Fish is the one area I don't personally see a good substitute, until the market tells me it is too expensive to continue eating.