Things I would do again? I don't think I could have done more research, but the problem is that it is not a culture that uses the internet to communicate (which I didn't find out in my internet research

. Personal relationships are key and you find out more about what is going on in your area through Associations and Expat clubs. It will take an effort to meet people but try to get to know the French as they are very sincere and kind when you are their friend. Think of hobbies you enjoy and at least that way you have some passion in common with the people you meet.
As for working... don't expect to work. It is difficult enough for the French right now, and I have found Paris an extremely difficult place to find work. I am not alone as many expat wives who moved here have said the same thing. Maybe you will be lucky, but I would focus on volunteering and enjoying the culture. If you need your income to have a decent quality of life, than no, sorry, don't move here.
I would suggest getting out of Paris often to really explore the country. Paris is not France and France in not Paris. It would be like saying New York is the United States, which it is clearly not. If someone went to the US and only lived in Manhattan they would not have gotten a flavour for the entire country. Transport is easy and inexpensive to take advantage of the trains to see other areas.
Oh, and as I mentioned in my Sunday Shopping post, forget about your ideas of good customer service or convenience. Just let it go now. Really, just forget about it

Stores are closed Sundays and many shops are closed Mondays as well. And banks take an hour or two for lunch so they close too.
I see that your post lists you in Denver. If you are sporty, or enjoy the outdoors, Paris is NOT a great city for that. Joining a gym is horribly expensive and although the bike-share program is popular, it is not like riding mountain bikes at home. Organic (bio) food is becoming more popular, but it is not what I would call a 'healthy' city. If you are not sporty and want to sit in a cafe with an amazing glass of wine and people-watch before you go to the Opera, which is inexpensive to see, then yes, Paris is your type of city