After having a drone for more than 2 years and fighting all sorts of battles with seeing what I'm doing in the full sun. the first accessory I'd spend money on is a good viewable  display. They're not cheap but the DJI CrystalSky works very well.
As Ringo mentioned, a decent landing pad is cheap and worth having. The Mavic2 is a lot better at returning to home accurately so you don't need a very big pad. A decent case that protects the drone and is easy to get things in and out of is another thing I'd buy again.