You can't hurt Crappie with a rod and reel.
Any lake that doesn't get fished pretty hard ends up with small fish taking over as they out breed their food supply.
Lake Fork and Lake of the Pines here in Texas are good examples of what it takes to grow big fish.
All winter long it is against to law to throw back a crappie no matter the size and they will hand you a $200.00 ticket if they see you do it.
Both lakes get tons of pressure.
They are arguably two of the best lake in the state for big fish.