I just bought my second copy of slay to play the network version with my girlfriend.
We play with two humans and up to 4 computer players.
We feel that because we can see the identity of the player (in this case either human or computer) some of the fun is taken out.
Because we know who our main apponent is we -depending on our mood-either attack them directly or deliberatly do not attack them.
Adding a "hidden identity" mode will most certainly make the game more interesting for a 2 player mode.
-No icon on the player to indicate it's his turn.
This last characteristic would be the most difficult to realise. One way would be to make the computer's turn as lon gas the average player. But that would slow the game down. I feel that the best way to do this is to not update the island during play. You play and when you finish the other players will take their turn. At the beginning of your next turn the screen is updated with all changes made by the other players in a single refresh. This might be challenging to program though because different human players will have different island statusses.
I think, due to the time difference, it will become obvious within one turn or so who the other player is.