Hello.
So Ynfinity brought up the good point of consistency. Typically, you'll want multiple copies of the key cards in order to draw them more often. Not only that, but the theme needs to be consistent as well. Having and Elf deck, for example, won't benefit much if you also include some Vampires. I think before doing anything else, you need to figure out a theme a little bit more. With that said, I'm going to list off some powerful cards that are typically seen with token decks.
A great card for tokens is
Intangible Virtue. A very basic anthem effect, but also very powerful. You will absolutely want this in a token heavy deck. Because this deck is mono White,
Honor of the Pure is another nice card to take advantage of.
Hero of Bladehold is a strong card in tokens. While 4 mana might be pricey, being able to create tokens with each attack while boosting all of your tokens can be very powerful. You can also take advantage of some Planeswalkers.
Elspeth Tirel,
Elspeth, Knight-Errant, and
Elspeth, Sun's Champion can all be powerful cards.
Other useful cards can be
Brave the Elements, which can help you finish out the game,
Path to Exile, to remove some threats, and
Timely Reinforcements in case you are falling behind.
Now, the most popular token deck in modern is Black White Tokens.
Lingering Souls can be fully utilized with the flashback cost. Black gives access to hand disruption, which can take our opponents key cards that can really mess tokens up.
Thoughtseize and
Inquisition of Kozilek are both wonderful cards here.
Bitterblossom is a very nice card that gives a constant
supply of tokens every turn. We also get another buff card,
Zealous Persecution. This can give that extra amount of damage and sometimes kill some of our opponents creatures.
Fatal Push is another spell to remove more creatures. Finally, we have access to another Planeswalker.
Sorin, Lord of Innistrad, and
Sorin, Solemn Visitor, can both be strong cards for tokens.
With all of that, I think the biggest changes need to come from the goal of the deck. With various one offs, there isn't a consistent goal that can be achieved. I suggest looking at the cards you enjoy the most or what you think are the most powerful and building around that. Hope this has been helpful to you. Good luck!