My tips, mostly from my previous experience with RC aircrafts and MRs. Just 5 quite cheap, simple and common items I believe make a huge difference in your flying experience, adding practicity, convenience, performance/safety or just plain comfort:
1. Inspire 1 tablet support (yes it is much, much better and totally worth the investment).
2. A neck or shoulder strap (every RC hobbyist knows how useful those are. Buy one and never look back).
3. Cambond cables (come in many lenghts including a 30cm good for iOS/Android AND are incredibly sturdy).
4. A hardcase backpack (DJI´s own is perfect but there are other good options too).
5. Prop balancer (again anyone with RC background will attest to the importance of this. Get a DuBro right away).