I, too, agree that the dominance of each discipline (ladies', men's, pairs and ice dance) will rotate among different countries.
One thing that I am surprised is your assertion that the Russia would dominate ice dance after Sochi (2014). It is true that Russia has been busy cultivating promising young talents. However, I believe that the Shibs are nothing but consistent. What I am also most impressed about them is their ability to raise their game; they improve on their programs throughout every season. I personally believe that the Shibs have made greater improvement than the Russain heir apparent, Ilinykh/Katsalapov. For instance, though I/K bested the Shibs at 2010 Jr. worlds (Gold medals vs. 4th place finish), the Shibs came out on top at every match-up during the 2010-2011 & 2011-2012 seasons.
Also just like Russia, both US and Canada are blessed with deep pool of talents with many promising up-and-comers.
North American ice dance field have one more intangle advantage: powerhouse coaching teams. For instance, two of the Michigan skating clubs (Arctic Figure Skating Club in Canton & Detroit Skating Club) boast the top five world ranking ice daning teams (Davis/White, Virtue/Moir, the Shibs, Pechalat/Bouzart, & Weaver/Poje). As these coaching teams' stars rise with their high quality ice dancers, these schools further attract talented and ambitious young skaters, including top foreign teams.
There is a tremendous advantage in training with top skaters. They try to push each other to higher levels, as we have witnessed wonderful rivalry between D/W & V/M. Young skaters can also aspire to work hard when the "pinacle" of your field is skating right next you! Hence, 2011 US jr champions (Lichtman/Copely) train in Canton whereas this year's champtions (Aldridge/Eaton) train in Detroit.
Furthermore, North America have recently become "mecca" of young and talented foreign teams in which there are few ice dancing resources and tradition in their native countries. The reigning Lithuanian champions, Tobias/Stagniunas train in Canton while Australian champions (OBRIEN/MERRIMAN) work hard in Detroit. In Canada, Spanish champions (HURTADO/DIAZ) had just signed up with Dubreuil & Lauzon while the young Mexian champions BRUHNS/VAN NATTEN have been busy training with David Islam, the coach and the father of Islam and his partner, Paul.
Ironically, the rise of North American prominence was also partly due to the decision the Russian federation made. RF had "encouraged" their promient coaches to coach top Russian skaters "first and foremost" for Sochi. Continuous coaching of foreign skaters were not "prohibited," but we all know what it meant. Hence, I/K no longer have an opportunity to train along side Pechalat/Bouzart. As the "top dogs," I am certain that I/K are getting all the necessary coaching from Morozov and his assistants, but I also wonder what they might be missing instead...
In general, I question how much this kind of isolationistic policy would be successful. I'm sure we will find out the speriority of one approach compared to another by Soch and beyond. It would be quite interesting.