Shuffling counters around is relatively unexplored design space in Magic and lets you do funny tricks, like moving finality or shield counters around
I can mostly think of Makeshift Munitions, Energy Refractor, and Network Terminal
Practice mode allows you to do just that: practice against an AI bot to test out your deck and see how it plays against an opponent
Cards that ramp are varied and numerous, including: Cards that put extra lands into play, like Rampant Growth Cards that tap for mana, like Sol Ring or Birds of Paradise Cards that reduce costs, like Goblin Electromancer Cards that produce short-term bursts of mana, like Dark Ritual or Dockside Extortionist Ramp is an essential element of Commander deckbuilding
From what I've heard, they cut open the card savers when taking the card out so pull tabs aren't necessary for PSA