Something else one can do to add some "life" to the game is to add a Critical Hit and Critical Fail card to the stack. Here's an example of something I'm going to run my player through soon.
EX:
4 players encounter 4 Hobgoblins.
I'm going to add the 4 player cards and 4 cards for the HG's.(I prefer to use individual cards for monsters). Then I'm going to add 1 Crit Fail and 1 Crit Hit card. These critical cards apply to the next creature/player drawn...not using the additional cards for DEX modifiers.
Darvel the Fighter's card is drawn, he takes his action; next card drawn is the Crit Hit. Draw the next card and it's a Hobgoblin. He automatically gets a Crit Hit on whoever he's attacking...(continue drawing).
One could create/add so many variable cards to this form of initiative if you want to liven things up...you could add +1 cards for attack bonus, damage, saving throws, wild magic surge, etc.