Its like deciding between chicken nuggets or a chicken sandwich at Chick-Fil-A
[43] Every event is divided between a regional or international event
If an effect says that a permanent cant be regenerated, no regeneration effect will apply when that permanent is destroyed, even if the effect was put in place after the cant be regenerated effect
Having a way to sacrifice a creature just makes sense, since it gives you the option of attacking anyone with the creature and not really worrying about whether it will live or die
That said, my prebuilt upgrades do tend to have a game plan and wincons, so they could also be considered a 5, even though they are just upgraded prebuilt decks
They wanted to ensure it would heal an adequate amount to be useful yet not heal too much, otherwise a player could make a board full of indestructible Venusaurs