Each Magic card has a rarity and, as a general rule, rarer cards are usually better
Many of these are fast because they come out on turn one, but they're fragile, because most Commander games will see at least one Wrath of God or similar
Ragavan, Nimble Pilferer I believe is the best choice for your deck as it gives card advantage + some ramp
It also includes four preconstructed Commander decks, which allow Wizards of the Coast to explore Commander-focused designs that wouldn't work in a draft environment
You can generate a ton of mana if you're untapping something like Circle of Dreams Druid and if you cast it on something like Experiment Kraj, you can save it from removal, tap it again, and deal some damage
The tribe has a very strong aggro element, and it's one of the few tribes to chart anywhere today that can actually build a good aggro deck