Take something distinctive to tie to the basket. Most
ECVs look a lot alike. Makes it easier to find when cast members move them. Mine is pink but we have "lost" it when eating. I do not try to take mine inside at restaurants or restrooms.
Take some light up sticks or such for nighttime. Makes it easier for others to see you. Check the dollar store for those treasures.
Take your key when you leave it. Cast members can "pop the clutch" to move it if needed.
Stay away from the trolley track at MK. Front wheels get stuck in those.
Turn off the ECV during parades or shows. Saves on battery life.
Rent from an outside vendor. If driving, be sure to get a scooter that will break down into parts you can lift into the car. I like Walker Mobility but a lot on the board use
Buena Vista.
Consider getting a handicapped parking tag at home. Makes parking easier as ECV and trams don't go together.
Toughest que line for ECV is Nemo at Seas in EPCOT. There is a back door (exit) that I use and just skip the ride. The combination of light outdoors to darkness and very tight turns makes this ride difficult with an ECV. Since I tend to watch the fish for a long time, having my own "chair" is a big plus.
Longest lines when you hurt is Soaring. I take my ECV into that one. CM will tell you where to park in theater.
Bring a garbage bag to cover the controls if it rains. Fold seat down too when you leave it.
Sorry you had to join the ECV community. I remember my first ECV trip. I felt a bit lost. Just ask a CM any questions and have a great time.