Consider where your going to carry your tools to change a flat. It’s takes 3 combination wrenches to change mine because front and rear axel nuts are 15mm or 17mm and the derailleur has its own nut. Then you’ll need to carry an extra tube, patch kit, nitrite gloves, a microfiber cloth, a multi tool and of course a Luna ePump. ))
That’s about all for flat repair. I carry a $1.99 Lowe’s plastic drop cloth that will cover my bike and my self in case of a heavy downpour rain event. How bout 4 bungees of 2 different lengths, or cargo straps, to strap large items to your rack when necessary?
I carry my 12.9" iPad Pro and my iPhone along with charging cables and a charger for each because my iPhone is lightning and iPad is USB-C. I carry a 4 cell - 18650 Li ion battery bank to backup both devices and power my headlight. I prefer to power supplemental devices on separate power supplies than off my main battery. My tail light has a single 18650 cell. Something I learned from aviation.
You’ll discover all kinda of stuff of your own preferences, needs and wants once you start outfitting.