Wow man, 4 years away from your wife. That must be so hard.
I wish you could rejoin her soon my brother.
Look, I would advice you to make the profile with your wife. Use the CRS Score calculator:
(
http://www.cic.gc.ca/english/immigrate/skilled/crs-tool.asp )
to see how much is the score going to be. If it is in the 410-420 range, then you must not worry, I think you have good chance.
If you can, do so, and tell us how many points you get. Of course, if she hasn't, I would advice for her to take the IELTS, and if she has any university degree, then she should do the ECA, so that you get as many points as possible.
If the score falls in the 400-410, then you can try to secure a NOI and have that backup plan to use if scores go up again.