I live here and truly feel for you. As far as I'm concerned, the best way is to stay on the south side of both cities using I-20 all the way thru. If at all possible, be west of 360 before 6AM. When we are traveling east from Ft. Worth, we leave at 4-4:30am. Just the best way to do it, particularly when your pulling a trailer. When we are returning from the east, I've been known to cut south on US67 and then return north on I-35W just to avoid most of Dallas and the areas around Duncanville and Grand Prairie.
Just my 2-cents.
Happy Camping!