I use a hearing-aid in each ear too, but I have to take them out when riding, because wearing them with a crash-helmet is too uncomfortable. Fortunately I can still hear the engine, and my bike's exhaust is loud! I can really understand your problem though, because there are always difficulties when you can't hear what everyone else can hear. My hearing-loss in in the higher frequencies, and my aids correct this very well but they go to town on the sound of my engine, making it sound like a bag of nails when everyone else tells me it sounds great with hardly any mechanical noise at all.
I can't help you with approriate speeds for normal gear-changes because I have a 350 cc with a 4-speed box. But we learn to compensate for our hearing-loss by using other indicators and your Electra is a new bike to you. I'm sure that given time, you'll get to know where you are in the rev range, and what gear you should be in. Enjoy the bike!
Tom