We had the same concerns 5+ yrs ago when we first got our 33ft motorhome, and a few months later also towing an F150 Toad. We have taken the west bypass early on only once or twice in all that time. Never the east bypass.
We have been thru the big A dozens if not scores of times now.
And we just go thru town come hell or high water. We usually embark with a plan to go thru at night well after rush hour but coming home is usually daytime and have been in bumper to bumper and construction/accident stops or creeps several times. And we have been stopped for construction even at 10-11 PM. So it doesn't really matter.
Just pay attention, get in a middle lane (or the HOV lane if you have 2 people or more where it exists), use GPS or know your route, don't go too fast, be ready to brake/stop/creep, don't change lanes a lot, use your turn signals if you do, have your navigator check mirrors and help spotting when needed, be polite with others in big vehicles and most of them return the favor. Just following a truck is sometimes a good choice if you have the patience. But stay back enough to see the signs so you don't accidentally get on I85 (don't ask)! Let the cars go around you if they want to go faster.
PS: DW doesn't drive the rig. If she did, we'd probably take the bypass.