It works ok, but I think it could be tuned up just a bit.
There's three things I'd like to do that are all connected:
1. Spread out the responsibility for tracking who's turn it is.
2. Use a big-visual cue for keeping track of who goes & when.
3. Insert a mechanism that allows for some greater player to player strategizing.
You know how things usually go with the turn-by-turn initiative system? The GM tells the first player to go. The first player resolves their action and tells the GM that they are done. Then the GM tells the second player that it's their turn.
I think that we can make the system a little less cumbersome by asking the first player to be responsible for informing the second player that their turn has arrived. Why does the GM have to moderate that announcement?
When we played those few sessions of Agon, we used playing cards to 'label' each player's turn. I did something similar, but less effective, to that in the last playtest. I'm thinking I'd like to go back to the playing cards, and even come up with some kind of little stands for them, so everyone at the table can see what your initiative score is. This would also make it easier for the first player to identifiy the second player, facilitating that change of responsibility.
Finally, I think it would be totally cool if players were allowed to "swap initiative". Player one wants to go after player two? Why not? They just swap their initiative cards before either one has acted in any particular turn. Combined with the Awesome Token system, players can now arrange themselves for the most interesting combinations. But the initative roll remains important for determining where the monsters go in the order.