With Sheoldred, the Apocalypse, there is both the showcase treatment and a Phyrexian version
Seven mana is a big ask, but in combination with Sun Titan, Karmic Guide, Burnished Hart, Solemn Simulacrum and Fetchlands, you can recur your whole board constantly
Forcing your opponent to sacrifice can be powerful as it gets around hexproof, indestructible, and protection
If a game of Commander lasts ten turns, and you have no way to increase your card velocity, you'll only end up seeing 17 (opening hand of seven plus drawing one card each turn) of the cards in your 99 card deck
Batterskull Courser only gives one life per land made, usually just one per turn (although it does mitigate sac lands well as well as having great synergy with the shuffle!) and not always even that