I worked in the NWA training building and my question to you is would you be an ATI or a simulator instructor? I don't think they hire sim instructors off-the-street; they are all NWA line pilots who became instructors.
The ATIs that teach groundschool have some time to wait before they can even get a chance to fly the line. They are after all of the furloughed pilots are recalled (currently about 500 and maybe more soon).
If teaching groundschool is what you want then go ahead and become an ATI at Northwest. If flying is what you want, keep doing what you are doing right now and go with one of your other two options that you mentioned.