The leverage is a lot better with the trap bar, so it's possible to gain maybe 20% on your pull after a couple of workouts, but taking into account your height it might not be that much for you.
depending on how you do the exercise it can pretty much become a 1/2 squat with the weight in your hands, which will work the upper back a lot because you're pulling more weight, but the angle of pull is significantly different so the lumbars dont get as much of a pounding. Grip shouldnt ever be an issue with a parallel grip, if it is then you have problems that need addressing.
don't expect much, if any transfer back to real deadlifts if you switch back.