As far as I know (not far enough!), a Leader or admin has to create project pages. So if you want to lead up a subproject, drop me or Lianne a line, and we'll do it. I'm excited that you want to take on New Brunswick and Alberta. New Brunswick is huge genealogically, and Alberta never gets enough information put online.
I'm with Lianne on creating subprojects as interest comes up, because someone has to curate the information and a placeholder would just kind of let it sit there like a lump. (Besides, regular projects are only created after there is sufficient interest, so subprojects should be the same. Fortunately, "sufficient interest" in a subproject is one person, and the main project leader.)