Niambi, Esteemed Speaker has all the elements of being a solid card advantage general.
There are 40 Legends, nearing half of the deck. In this manner you should have a Legend to discard to get the draw from Niambi, Esteemed Speaker ability.
Reanimation and Card Filtering
As you discard a Legend to get the draw, this deck takes advantage of the fact that it allows you to play some "big fatty" creatures, as often early on they are not relevant due to cost, but here we can discard them to filter through for more relevant cards for that stage of the game.
On top of this there are also ways of putting creatures from your graveyard on to the battlefield, so you make use of the discard to in fact help this plan.
Loyal Retainers, Karmic Guide, Emeria Shepherd, Elspeth Conquers Death, God-Pharaoh's Gift, Reya Dawnbringer can bring back any Legendary creature.
Sun Titan and Teshar, Ancestor's Apostle will hit 3 converted mana cost or less, so not aimed at the bigger creatures, but none the less makes use of the reanimation theme.
Other cards that help you put cards into your graveyard are Emry, Lurker of the Loch, Jace, Vryn's Prodigy, Search for Azcanta, Geier Reach Sanitarium, Intuition, Jin-Gitaxias, Core Augur.
Bounce and Blink
Niambi, Esteemed Speaker can be cast at instant speed and she can return a creature to your hand.
There are a number of creatures that have "enter the battlefield" triggers for advantages, so you should be able to get additional value from this.
Thassa, Deep-Dwelling also helps with getting additional ETB triggers from your creatures.
You can of course just use Niambi, Esteemed Speaker to save a creature from removal by bouncing them back to your hand. So if you wanted to be patient you can just leave her in the command zone, holding off removal from opponents not wanting to waste their spells.
Card Draw
Drawing another 2 cards per turn as you get into the middle and later portion of the game is pretty great.
You do need to discard a card, but as already pointed out you can use this to your advantage, and there are 11 Legendary Lands in the deck as well, so "flooding" really isn't an issue as you can filter lands often.
On top of Niambi, Esteemed Speaker there are additional ways to draw cards.
Jace, Vryn's Prodigy, Mangara, the Diplomat, Nezahal, Primal Tide, Jin-Gitaxias, Core Augur all draw you extra cards.
Control
Urza's Ruinous Blast can be used to clear much of the board, while retaining yours.
The deck is quite proactive, but there are a number of counterspells and removal as you are happy for the game to go long as you have such an amazing quality of cards.
Once you are casting spells and using Niambi, Esteemed Speaker activated ability, then you have a firm grasp on being able to handle the game.