In Geneva airport, out of Zurich airport

I haven't used Geneva, but Zurich has been excellent. For me, one of the biggest perks is the train station located at the airport. I rode trains in Switzerland but have always just had a small carry-on, so I can't give you info regarding how your experience would be with large suitcases. As with any train, you need to handle your own luggage & getting on/off the train.

Geneva airport is great. I've flown in and out a few times with no bad experiences. As for big luggage on the trains. Just be aware that as well as handling your own luggage there is limited storage for big luggage at the ends of the train cars. And if you leave your luggage at the end of the train cars you won't always be able to see it depending not he layout of the car and where your seat is located. If you can get your luggage to a size that would fit above the seat, I'd encourage you to do so.

We've flown in/out of both Geneva and Zurich airports many times with no problems. Switzerland tends to have excellent trains. It's one of our favorite countries to travel in using only public transportation.

I've been in and out of both airports. Geneva is a great little airport, a manageable size, and efficiently run. Zurich is also very modern and well-organized. It's Switzerland! That country knows how to run things. :)
I've taken full-sized suitcases on Swiss trains and had no problem. Just stow it at the end of the train in the space designated for that purpose. Not a problem.

Thank you all for good information :)

Most train cars will have storage racks at one end. According to signage I saw, they also recommend stashing your bags in the inverted V shape caused by seats butting against each other. If the car's not crowded, we just kept our bags right next to us. Plenty of options. Just don't put them up on the seats that's not nice.

The Zurich airport station is only steps away from the terminal, in a big shopping arcade. For those important last-minute purchases for the folks back home.