The following script is nothing fancy, but helps increase workflow by putting several common tasks together.  This will animate a layer from a scale of 0,0 to its current size, with a nice bounce effect.  See details below:

/************************************************************
To use:
Run script for any layer

The script will:
 Set a 0,0 scale keyframe at the inpoint of the layer
 Animate the scale to the current size with a little bounce at the end
 Turn motion blur on for the layer
 Turn motion blur on for the composition (if it isn't already on)
 If the layer has a mask on it, it will re-center the layer's anchor point so that it scales-in evenly
 
You can then:
 Change the timing of the keyframes
 Change the amount of "bump" by tweaking the scale values
 Move the anchor point as needed
 Anything else you may need
 
***************************************************************/

function fadeLayer(myLayer)
{

 //If there is a mask, reset the anchor point
 if(myLayer.property("mask").numProperties > 0)
 {
  var initialMask = myLayer.mask(1);
  
  var point1, point2, point3, point4;
  var vertsArray = initialMask.maskShape.value.vertices;
  if(vertsArray.length == 4)
  {
   point1 = vertsArray[0]; 
   point2 = vertsArray[1];
   point3 = vertsArray[2];
   point4 = vertsArray[3];
   
   var maskWidth   = Math.abs(vertsArray[0][0] - vertsArray[1][0]);
   var maskHeight  = Math.abs(vertsArray[1][1] - vertsArray[2][1]);
   

   ap1 = point2[0]+maskWidth/2;
   ap2 = point2[1]+maskHeight/2;
  
   pArray = new Array(ap1, ap2);
   
   var diffPoint = pArray - myLayer.property("Anchor Point").value;

   myLayer.property("Anchor Point").setValue(pArray);
   myLayer.property("Position").setValue(myLayer.property("Position").value+diffPoint);
  }
 }
  
 myProp = myLayer.property("Scale");
 inPoint = myLayer.inPoint;
 outPoint = inPoint + (8/12);
 bouncePoint = inPoint + (6/12);
 
 outKey = myProp.addKey(outPoint);
 myProp.setValueAtKey(outKey, myProp.value); 
 
 bounceKey = myProp.addKey(bouncePoint);
 myProp.setValueAtKey(bounceKey, myProp.value*1.05);
 
 inKey = myProp.addKey(inPoint);
 myProp.setValueAtKey(inKey, [0,0]);
 
 var ease = new KeyframeEase(0, 33);
 
 myProp.setInterpolationTypeAtKey(1,5013);
 myProp.setInterpolationTypeAtKey(2,5013);
 myProp.setInterpolationTypeAtKey(3,5013);
 
 myLayer.motionBlur = true;

}

// make sure a comp is selected
var activeItem = app.project.activeItem;
if (activeItem == null || !(activeItem instanceof CompItem))
 {
  alert("You need to select a layer before running this script");
 }
else
 {
 // make sure at least one layer is selected
 var selectedLayers = activeItem.selectedLayers;
 if (selectedLayers.length == 0 )
  {
   alert("Select at least one layer before running this script.");
  }
 else
  {
  app.beginUndoGroup("Scale Layer 0 to current with bounce");
  
  selectedLayers[0].containingComp.motionBlur = true;
  
  for(i=0; i<selectedLayers.length; i++)
   {
    fadeLayer(selectedLayers[i]);
   }
   
  app.endUndoGroup(); 
   
  }
 }