Renting a car just north of Paris

You can pick one up in Rouen. We drove from Honefluer to Rouen in April. It's a nice easy hour's drive.

Rouen is a good suggestion; you could also check options in Le Havre - longer train ride but just a 25 min drive to Honfleur.
CDG is not a good option to head to Normandy, the best traffic-avoiding route around the Paris region is not straightforward.

Edited to add, that if you'd rather not take the train, you can also rent cars in the Porte Maillot area and in the La Défense area. Both are easily reached on line 1, and leaving Paris via Neuilly-sur-Seine, la Défense and the A14 is easy.

Second edit: this is all assuming that you are staying in Paris. If you want to travel right after landing, please take the train first for your own safety and that of others.

Veteran Traveler - was it hard to navigate traffic out of CDG? I’ve always read to not drive in the major cities unless you have no other options. Especially with jet lag after a flight. I don’t know that I would feel safe driving in those situations. I still prefer taking a train out to a town that requires the least amount of driving in traffic.

I have also driven out of Paris—both CDG and a Hertz office in Porte Maillot (just inside the periphery). Driving from Paris is not the same as driving in or through Paris. I didn't find navigating my way that difficult. But rush hour is very busy until you get off the periphery roads. Plus, if you are leaving after arriving on an overseas flight, don't underestimate how dangerous jet lag will be.

I took the train to Rouen and picked up a car there near the train station.