All are good points, except #1. This engine has all electronic ignition. There is no distributor cap, rotor, or spark plug wires. This engine has a coil pack, with three coil wires and three high tension leads that "piggy-back" to the next cylinder (each coil wire is responsible for firing two cylinders).
As the coil wires are made of solid copper, they rarely go bad. So the suggestion here would be to replace the three resistor boots on the three coil wires - about $7 each. An engine with a miss is usually due to a poor connection between one of the boots and its coil wire.
My best guess is the problem is still a fuel pressure / supply problem.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".