I finally freed up enough time to put time into an battery operated electric reel so here's some questions. Do you need a water proof drag. Do you feel that a Shimano Sedona 4000 would be a good reel to use. the Sedona is less than $60. are there other spin reels for up to 10 lb. line that are basically universally recognised as an over-all good affordable reel that I should consider.
Okuma has a wide selection of reels at various price points.
Waterproof drags are important for saltwater fishing because you have to rinse reels after each trip. They're not a critical feature for freshwater use (unless you plan on dunking your reel frequently).
Today's graphite-body reels are excellent, but aluminum frames offer greater rigidity/durability for the higher price--could be a factor when mounting a motor.
I like Shimano. They are very smooth operating reels. Are you building this for yourself or will you be selling them? I'd be very interested in purchasing one as long as it had a speed control on it. I am using the electra-mat spinning reel. It's big, to big. And has no speed control. It's kind of fast for Crappie fishing.