I see a lot of people venting their frustrations about French procedures - Tax, driving licences etc.
Perhaps I'm just lucky, but I have never had a (really) bad experience.
The guichet godesses I have dealt with have always been helpful, polite, and surprisingly pragmatic.
Autoentrepreneur - registration completed in ten minutes in the URSSAF office.
Carte vitale - One form filled in, photos taken, card received a couple of weeks later.
All of the above completed over a cup of coffee with a smile.
The only slight frustration I had was when I received the taxe d'habitation for my old address, and could not find the exit inventory to prove I had moved. I returned again a day later with some other paperwork and the problem was solved.
I think a lot of bad experiences stem from the fact that staff are so used to people shouting the odds at them that they begin most meetings with a slightly defensive approach.
They are also programmed to want all the paperwork to be "just so" - if anything appears irregular they will generally panic a little. This is where a little schmoozing can help to ease the situation, rather than a rant about "bloody French ...".
I think the key piece of advice I would give to anyone is, if you need to get something done, go there in person! Phonecalls generally get you nowhere, and it's hard to mount a charm offensive over the blower.
Also, before going to any administrative office, read carefully what paperwork you need to take - The person in front of you will be ticking off the same list!