Bilt Hamber Auto Foam is still my go-to foam. I find it a very useful pre-wash step, personally.
Also Bilt Hamber’s Touch-Less is worth a try. Especially at this time of year when your car might be more dusty then truly grimey. I’ve found it’s possible to use it as a fully ‘touchless’ system to get the car foamed, let it dwell, then a power wash rinse. Without any contact on the paint whatsoever.