Here is what I use:
"This is going to be a ________ takeoff from runway ________. We will rotate at ______ and climb out at _______ until 1,000 AGL. Any engine abnormalities or loss of directional control before rotation and I will bring the throttles to idle and apply max breaking to stop the aircraft. Engine failure after rotation with usable runway I will bring the throttles to idle and land on the remaining usable runway. Engine failure after rotation with no remaining usable runway I will maintain directional control and climb straight ahead. As soon as possible I will identify, verify, fix or feather.
That's exactly the same briefing I make when there's another pilot in the seat next to me - even if it's in a 152.
I think one important part of the safety briefing is to determine who is PIC and will ultimately control the aircraft during an emergency. That way there's no wrestling and there's also a pilot ready and able to back you up on the checklists.
CRM shouldn't only exist in multi crew ops.
Just a thought..