Though of course you can also use Keelo to sacrifice or play any unit in the deck.
Notes: You usually want to get to PPPSSS influence before playing cards like Gustrider and Sporefolk in case you can discard Felrauk the Outcast.
Justice influence in your opening hand is not that important. Having dual powers is usually better.
Having draw and discard effects is also important when evaluating opening hands.
Using Keelo to play a shadow unit will trigger Vara
Discarding Felrauk will trigger Vara
Sacrificing Naoki gives an exalted weapon.
Sacrifing Icaria causes the opponent to discard spells.
Sacrificing Azindel puts him in the void for Vara to immediately replay
The ShiftstonedEternal Power Calculator is a deck-building tool that visualizes your odds of drawing enough Influence and Power based specifically on the cards found in your deck.
An even Keelo Vara list is fine too, but I think it would be less consistent.