The real impact comes from Angel of Invention's ability to Fabricate 2
Im talking about the ones that are hard to find, hard to grade, and even harder to let go once you have it in your hands
Loots cheap to cast, and if we can stuff the deck with other cheap nonland permanents (oh, like that Senseis Divining Top!) we can effectively dig through our library for a spell to cast each turn and hopefully re-ramp ourselves back up to a serviceable amount of mana before our opponents can
All other rules and effects that check power or toughness use the real values, even if they cause damage "equal to a creature's power" to be dealt
Deino #108 Pokemon Darkness Ablaze Keep track of your collection value over time
At first, this seems a rather massive change, as surely there's quite a possible shakeup that comes with adding a whole new card type to the pool of legal Commanders