I have a few more questions if it isn't too much trouble for you:
1) Does same day travel still constitute a day in Canada's eyes? For instance, while she's pregnant if I go check on her everyday after work and then return to my home in US that same night, is that still considered a "day in"? I would only do sleep overs on the weekends. Or does every-time I cross the border regardless of how much time I spend still constitute a "day in"? Obviously with her being pregnant I would like to be there to support her as much as possible but still be well within the law and not risk anything. I know she has also mentioned I can apply for Canadian PR but not sure yet...
2) If we apply for her I130 ASAP, will that prevent her from visiting me occasionally in future or her getting her I94 stamps renewed? Her evidence of ties to Canada would be her job in Canada, her pregnancy OBGYN appointments in Canada, and her apartment in Canada (although I know a house is much stronger evidence). She also recently applied for Canadian citizenship so not sure if that also can be used as evidence of strong ties.
3) Does USCIS care how soon you file an I130 application post-marriage? For instance, if we want to wait a bit for whatever reason (still discuss our future plans of living in US vs Canada, ability to do IR1 instead of CR1, etc), is it OK to do so? Obviously I know that will just delay things but I'm curious if that raises any red flags in USCIS's eyes? Do they generally want to see people file immediately post-marriage? Is it ok to wait a bit for the reasons I mentioned above?