I’d get rid of Chicago and Boston and add Shanghai and another one in Kenya or Ethiopia. China will quickly surpass Japan and the US in terms of marathon finishers. Also, it would help the sport if more non-Africans got to know a bit about the culture of Kenya or Ethiopia first hand and build some personal connection by traveling there to race.
We asked the WMMs what is the "stringent criteria" they use to determine a major as it's never been publicly revealed.
Do you think they should use athlete criteria like the IAAF uses to determine Gold, Silver and Bronze Label races? They say for a race to be a Label race, you need an international elite field with the following requirements of how many and how fast they should have run:
1) "An International Elite Field with a minimum of 6 men + 6 women (for single-gender races, 7 athletes) with the relevant Status as defined below, representing a minimum of 4 different nationalities and, in Silver and Gold Label races, a minimum of 2 IAAF Areas, one of which must be the Area where the race takes place (for the purpose of this rule, Oceania and Asia shall be considered one area, South America and NACAC shall be considered one area)."
2) Meeting a time requirement for distances from the 5k to the marathon OR finishing in the top 10-25 of different world championship races. The requirements get slightly easier moving from Gold to Silver to Bronze Label races.
Or to make it even easier, just choose a consistently Gold Label race in the area they want to add a WMM? That makes the "stringent criteria" high quality.
(See section 3 on page 2 of the PDF for details)