Anyone who nit-picks over indicators has too much time on their hands (no pun intended).
I don't care if your indicator has 2 or 3 strikers, 3 or 4 balls, 2 or 3 outs, or a running tally of how many hot dogs you've eaten at the tourney. As long as it helps you, rock on.
I've got 4 indicators, and all are 3/4/3/0-9.
And actually, in games where I'm the umpire AND scorekeeper, the inning wheel helps a LOT to keep track of runs.