Nico is fairly fragile due to having lackluster HP, 0 DEF & +1 EVD. Avoid battle as much as possible unless you got some good hypers in hand!
Gift cards are always beneficial for Nico due to her passive, and she does not receive any detrimental effects from them such as preventing Norma. Unlucky Charm in particular is a good pick, since it can be passed to Nico even if she wasn't the one who drew it.
Since Nico can use Miracle Walker to turn her entire hand into Hypers, Mimic can be allow you to receive many powerful Hypers at once there is an opponent with a powerful Hyper in the game.
President's Privilege can be used before Miracle Walker to negate its star cost, as well as the star cost of any expensive Hypers that were generated on that turn.
Unlucky Charm in particular is a good pick, since it can be passed to Nico even if she wasn't the one who drew it.
Miracle Walker to turn her entire hand into Hypers, 
Mimic can be allow you to receive many powerful Hypers at once there is an opponent with a powerful Hyper in the game.
President's Privilege can be used before 
Scrambled Eve, 
Flamethrower, and 
Present Thief can be used to remove both Gift cards and powerful Hypers from Nico's hand.