I think it'd be a nice touch. When you're driving, it's hard to look up at the screen to see the remaining time. (I don't know how many audible bells there will be this year: just 15 sec mark, just 10 sec mark, or both)
It'd be nice to have it display on the dashboard with indicators relevant to minibot deployment.
That being said, I don't think there's any reason to automate or regulate deployment. As long as the driver knows how much time they have, you should be able to trust them to do what they want. You wouldn't want any "smart" system to get in their way.
Still, it'd be tempting to have the last 15-20 seconds completely automated.
And for those thinking of implementing a timer, make sure to start when teleop starts! The period between auto & teleop can change by a few seconds.