A bit late to the party, but I also throw my 2 Cents (or 0.02 EUR) into the hat: In my experience as a user of equipment (and designer of electric distribution throughout a house etc.) and person that does Appliance testing, Leakage currents are nowadays quite important.
I have in mind that EN60950 (and the successor EN62368) mandates those rules. In the national VDE 0701-0702 (germany) I have to use for checking appliances after they have been bought and are in use, leakage current on the PE is allowed to be at 3.5 mA, touch current 0.5mA.
As a RCD with 30 mA is mandatory in newly built electric installations, the combined leakage of poorly designed devices/appliances can impose some problem, because they are pre-loading the circuit. As a RCD with 30 mA rated differential current is able to act between 15 mA and 30 mA, it can be "blown" by several poorly working stuff that add up a bit.
Probably a ready-made PSU with PFC would be the easier way to go. Also, if commercial buyers are the target, in due to regulations they are required to ensure that the total power factor towards the energy network provider is within a certain tolerance- and every device that causes unwanted network feedback is no good.
Question: How are the 3.5 mA determined/to measure? "Only" TrueRMS, or with the so-called 50Hz filter according to EN 61010 table A1? Here the body sensitivity is taken into account (DC and high-frequency AC are less harmful to the human body as AC 50Hz) and with the described circuit filter the measured trueRMS value is somewhat normalized.
A PAT tester from the big manufacturers as Gossen Metrawatt, Metrel, Megger, Fluke etc. has this built-in, so the values those testers will show are somewhat lower that if a leakage current is measured by multimeter.