19 Days In France--- Seeking Advice

Due to an ongoing crackdown on illegal rentals you'll hear this from many:

Make sure your Airbnb rental has a 13 digit registration number. Otherwise it may be pulled off the market leaving you short a place to stay. There are many forum threads on this that will help you.

Sounds like you'll have enough time in Avignon to take a quick day trip to some of nice nearby towns. There are several hotels adjacent to Avignon central Station (what they lack in charm they more than make up for in convenience). Arles is only 30 minutes by train away. If you're flying back from CDG consider staying at a hotel adjacent to CDG that night. There are several direct trains from Avignon TGV station directly to the CDG TGV station

At first glance it looks OK to me, but then...

For all the "short stay" locations (Bayeaux, Beaune, Annecy, Avignon...) remember that you will not magically transport yourself instantly from location to location, each time you move you will burn 1/2 a day with the mundane tasks getting out of one place, finding your way, getting in to your next place, etc. So, for example, your "Day 2-3: Bayeaux and Normandy" really works out to no more than about a day and a half...you may want to steal a little time from your long-stay location (Paris).

You seem to be a candidate for a multi-city airline itinerary, saving the time and money of retracing your steps to the city of arrival. In the south, the big airport is at Marseille, an attraction itself and easy train connection to Avignon (which I love.) It will probably require a connection through a European gateway city, so that's I'd start in the south, working north to Paris and then home (with the chance of a civilized time of departure rather than 6 in the morning.) The trip requires a multi-destination search function; these are not a pair of one-way tickets.

And if you can plan your train trips to avoid the days in May scheduled for strike closures, it could reduce your worries (if the strike is still going on in May.)

You can get a TGV from Avignon direct to CDG airport, which might give you more time outside Paris.

In my opinion, that's far too long in Annecy. I would argue the town, if traffic and parking are not too horrendous, is worth an afternoon or a morning at the most. If traffic's bad I'd skip it. If I were on your trip I would advocate for going from Beaune to Lyon, and then on to Avignon.

Is this the 4th through 22nd train only or will you have a car for a portion of it? I assume the 2-3 part is with a car?

I would reconfigure to this:

1 - arrive and tgv to TOURS directly from CDG, pick up rental car, sleep in/near Amboise (check out La Chevalerie in the RS guide - can't beat the price - I've been there twice)
2-3 Loire Valley - 3 nights
4-6 Bayeaux and MSM (Normandy/Brittany) - 3 nights (Dinan (https://www.vrbo.com/6696515ha?unitId=2137891) and San Malo are wonderful too!)
7-9 Beaune (6.5 hour drive) - 3 nights (bike rides!) (https://www.vrbo.com/117299)
10-14 Provence - 5 nights (Pond du Gard, Luberon, Cote due Rhone, Arles, St Remy , Les Baux - http://carrieres-lumieres.com/en)
15 - drop off car, train to Paris
15-21 Paris - 6 nights
22 go home

I love Annecy (I've spent a week there), but there's more to do in the Loire and it fits better with your movement around the country. I'm suggesting >3 night stays in each place. I don't like wasting that first and last day.

I would finish the trip in Paris. By doing the south of France first you essentially waste a day of the trip racing back to Paris the day before departure. I find that ending a trip with that kind of rush back sort of takes the edge off the relaxation of the trip itself. Go from Bayeux to Beune and then head south and return to Paris to finish and be in the city of departure. If they have already booked the apartment then of course you have no choice but it is awkward scheduling.