Lunch place issues on arrival, departure days..car full of luggage

Check in times always are a problem when flights arrive mid morning. Often, you can drop off your luggage and come back later to check in. You'll need to talk with your landlord to see what his suggestion is. They often allow early check in if they've already cleaned the accommodations. Don't consider hitting the grocery store until after you've got settled in in your villa.
Sorry I cannot help you with places to get lunch and beat some time.
Just try to stick to Rick Steves' packing list for your suitcases, and you'll be all right. We've been traveling with carry on's for years, and can make an indefinite trip out of a 21" rolling bag each and a backpack.

You have a bit of a drive upon arrival, and I see your problem is that you want to stop for lunch, but are concerned about the security of your belongs in the car. If you get a hatchback-type car, it should have a sliding security cover, which will obscure your belongs; otherwise, put your stuff in the trunk and don't leave anything inside the main part of the car - not even in the glove box - and lock the car. I have driven in France on several trips, of 3 to 5 weeks and it is impossible not to have to leave luggage in the car at some point, but I have never had a problem, though there is always a first time.

One suggestion I have is that as soon as you can after getting the car, either find a place for lunch or stop at a grocery for some snacks. Unless you are on the Autoroute, you will be going through a lot of small towns and villages that are pretty much closed up from about noon to 2pm, except for restaurants, bars and cafes - and some of these serve food only from noon to 2. Even so, it can be hard to find a place to eat because many places aren't very inviting from the outside (but may be quite nice inside). More than once, we found ourselves unable to find a good place for lunch while on the road and without much to eat in the car - I even started to wish the Golden Arches would suddenly appear. If on the Autoroute, you can stop at one of the "Aires" where there is usually a restaurant, cafeteria or McDs, and you don't have to leave the highway. There is also often a boutique where you can buy snacks and local products.

Even on the Autoroute, I would be careful to hide all my belongings. Thefts do occur there. You might think about taking some of your suitcases with you, if you want to eat or visit the toilettes.

I wouldn't lose sleep over this. There's a big difference between Street parking in Marseilles and the pay lot at the pont du Gard. In fact, the pnt du Gard might be a good day 1 activity. Buy a picnic en route or eat there. Of all of the places I've parked the car in Provence, that seemed the most secure and you have to do something to pass the time.

Alternatively, drive to you place in St Remy, drop off your bags and then visit Les baux and Carriers Lumineers.

I don't worry about rest areas. You will see hundreds of Europeans whose cars are stuffed to the brim with stuff at the rest stops and nobody seems to care.

off an overnight flight we may not be very attractive :-)

Well, that's one issue you don't have to worry about. I stopped worrying about that kind of thing years ago, after our visit to Bourges the day we arrived. I drove from CDG to Bourges, where we were staying the first night, and by then it was time for dinner. We walked around town, and saw a place that looked very charming. Everyone was dressed pretty nicely and I was grubby after an overnite flight, so I was hesitant, but also hungry. So we went in, had a fantastic meal, and were treated incredibly well, including by the chef/owner who came out to pour our glass of Calvados.

As to worries about luggage in the car, I wouldn't be too worried in small villages or almost any restaurant parking area. The kinds of places this would be a problem might be outdoor parking lots near tourist attractions or on the outskirts of a town.

One tip for a bit of extra security for your belongings: make sure you do not open the trunk/hatchback once you've arrived and parked. In other words, if you're going to take something with you when you arrive, have it in the passenger compartment; if you are going to want to leave something in the trunk, put it there BEFORE you get to the restaurant or sight.

this last post...I get that...so no one sees you rearranging your vast assortment of valuables...:-)

I thought if I could find a nice casual Mas around Mausanne or Paradou that served lunch...the location would be more private, and we could still enjoy ourselves. Otherwise a trip to a grocery store and then a picnic somewhere...