Initiative-less combat?

[Curse]

For any group that is very rpg oriented and cooperative that might work beautifully. Any group that is not cooperative you will have problems with any system so no loss there.
How are you imagining several actions? Does every player get as many tokens as there are actions?

I cannot picture yet how you deal with enemy actions. If there is an ambush it should be clear that enemies act first. How do you deal with everything else? Will you also "just say" that an enemy will act now or will you have player turn vs. enemy turn?

Edit: sorry I misunderstood the 50/50 thing.
I am not sure how far that will work with an action economy. Take a group of 4 players. In normal 3.5 rules and mid-level characters you should have something like 8 actions per turn. If enemies can only take a turn with 50% chance after a player - what about a larger group of enemies? What about just one big one? Will he get 8 chances to act then?