Congrats on the new bike, if you like the rider saddle consider getting the Hepco Becker back rest with or without rack and get the pillion perch re profiled with new foam and cover for your passenger. That's what I did and the missus finds it really comfy and I got to keep my rider saddle, bonus. I would certainly go down that route before swapping out for a one piece touring seat, and probably a lot cheaper. Reference passenger floorboards, the Guzzi ones are quite large (and horrendously expensive) and you may find you catch your heels on them when putting your feet down. Have a look at kuryaken mini floorboards or get in touch with Todd for a 'one off'. Enjoy your new ride.
I was thinking about the trade off between my seat and hers so I ordered the Touring Comfort seat. I figure if it doesn't work out I should be able to sell it for minimal loss. I tried sitting on the pillion myself and found it to be "wanting" in the width dimension so while I agree that re-padding it would be an improvement I don't think it would be a final solution. I'm trying like heck to avoid the Corbin seat but everything seems to be pointing me there. With the way we ride it will be years before its broken in.