Just some hints and tips from my testing experience. Please add any others you think are worth sharing.
1. I've set the 3D Home View Looking Down from to 500,000ft, to give a overhead view similar to the 2D view. Great for seeing what aircraft are where.
2. Remember you can customise label size, contents, aircraft model size, etc. in the 3D preferences. I personally prefer a smaller 3D model, but play around with settings to get what's best for you.
3. Remember the Google Earth shortcuts: