I really like the idea of the complete collections - it's something that's different from previous dynasties. However, I agree it's complicated: as Marian said, steak and burger plants need supermarket ingredients as "seeds". So do cheese and egg plants. (Or use the ingredients that come with a fridge, I suppose - and I'm not sure about the chicken coop from the store. Can those eggs be planted? Not that that helps the rest of us
.) If it were up to me, I'd be inclined to allow plants grown from bought ingredients. You still need high gardening skill and, for some plants, opportunities to grow them. Maybe insist on perfect specimens for fish and plants? Although I don't know how someone could prove that they'd done that. Tricky, isn't it?
And there's the metal problem: people with WA can't get a complete collection without a dog/werewolf, display case tansfiguration or buying supernovium and compendium. As it stands, I don't think the rules allow any of those.
Marian, reading around this, it seems that the extra spawners unlocked by the butterfly collector challenge include will o' the wisps - although I'm talking from a position of total ignorance here, as a non-Late Night player.
Edit: Shirin, meant to say that I love your addition to the spreadsheet.
On the subject of moving rules, can 'moving heirs' take their LTHP rewards to the next world? It doesn't really make much difference in practice, since they could save up their points and spend them when they arrive, but it might be good to get that clarified.