I think you're spot on your evaluation. With the exception of the tongue weight. My guess is it will be closer to 1000lbs. Which puts you in a deeper whole. Also the door sticker is the weight as it leaves the factory as I understand. So the 1420lbs is what you have. I see it as you're about 325lbs over GVWR.
TW 1000
Family 360
ARE 190
TT battery 45
Propane 40
Front cargo 200
WD hitch 100
Total 1745lbs.
While being over GVWR by 325lbs isn't the end of the world, and doable if you're short tripping it on weekends. I would be concerned though that you're close or over and we're just using hypothetical numbers. They could be lower or higher. Not sure if the FG sided TT is less in weight or not. That could be a plus. Might be worth a call to Jayco.
I ran into the same thing when we had our TT and F150. I even had 1857lbs of payload. Snugtop cap plus all the stuff in the truck and a 7300lb TT with 900lb TW put the truck right at the 4050lb RAWR.