I went from a 10.5” Pro to 11” pro I and I will echo what others have said, it was a very marginal upgrade. I ended up spending just south of 600$ CAD (net; after selling my older device) on the new iPad and pencil, and I don’t think it was worth that difference in the end. A10X vs A12X made no difference to my OneNote, GoodNotes or Notability use. Both had 120hz True Tone and laminated display, 10.5” had slimmer side bezels actually, and both had more or less same cameras and ram, similar quad speakers, Touch ID was a bit more convenient than Face ID, no difference in wifi spec...I couldn’t simply justify what I spent the 600$ extra on. But in the end the deal was done and I had sold my 10.5” Pro so alas, I had to suck up that cost and found positive utility in the pencil 2. I won’t be making marginal upgrades in the future, and will wait for the next design or significant change.
given your trade in value worth, I wouldn’t think of performing any upgrade
Edit: though I see you decided to do so. As long as you’re happy with your purchase. Our opinions are just that; opinions. In the end you work hard for your money and you should spend it however you want, whenever you want a new device. Life is short haha. Enjoy your new device.