I’m with Slasher on this. Just get rid of hand signals.
The more I look into it, the more I find out that they all have the same origin, going from coaching signs to umpire signs to catcher signals. They were initially all implemented to accommodate deaf players.
Nothing wrong with that. In fact, MLB has a rare moment where it should be proud of the way it accommodated, and did so long before anyone else. But this peculiar origin does make the use of hand signals as a tradition feel a little less important...