You can pay extra mana to gain extra effects - almost like levelling up in D&D - with the Barbarian Class giving a creature +2/+0 and menace when you roll a die, and its final level giving all of your creatures haste
(Even if Mark Rosewater recently disputed the claim that Universes Beyond is primarily targeted at new players.) During the Final Fantasy set prerelease event, I played next to a guy who said he had sold his older brother's old cards to pay for a Final Fantasy play booster box and a Commander precon
As for the Energy shiny cards, they include Basic Lightning Energy, Basic Psychic Energy, and Basic Darkness Energy
If the creature is no longer a creature at the time it goes to the graveyard, you will still draw two cards if you controlled it at that time
Evolutions does a wonderful job of honoring cards of the past, as its lineup occupies space in a number of prominent strategies like Greninja, Vespiquen, and Mega Rayquaza
Land ramp hate like Keldon Firebombers is something we don't have a lot of options for in Magic and I'd love to see more of