Recommendation for American in France?

[bigjoec]

My wife and I travel to France once or twice a year, and I'm tired of worrying about crazy data charges.

Any recommendations on best way for an American with only an American credit card to proceed?

The must-haves are:
- SIM card doesn't expire (I want to use this for a week or so in May, and I want be able to top it up and use it again for a week next year, etc)
- Can be topped up, somehow, with an American credit card (I guess cash is okay, too, but not preferred)
- At least 3G speed on my GS4
- Allows tethering/mobile hotspot. (My phone's not dual-sim, and I want my US number on all the time. I'm going to put this card in an old phone and run it as a hotspot for our regular phones.)

The really-want is:
- Minimum hassle in-country, i.e. I'd like to not spend more than an hour or two of my time in France getting a hold of the SIM card and getting it working.

Other stuff is not that important.
- I don't need to optimize for the best price (cheaper is better, of course)
- I don't need blazing fast download speed (faster is better of course)
- Wider coverage area is better, but not critical
- I'm willing to go through a decent amount of hassle now, while I'm still in the US, to get things set. (But just this first time).

Any thoughts appreciated!

Best,
Joe