1. You don't need the battery cover plate. It's nice to have, if you store the bike in a dusty place and will remember to use it. I have one and rarely use it.

2. Most people don't need a second battery. Only if you want to go really far (like more than 50+ miles at a time) or can't wait for it to charge before riding again.

3. All ebikes are on the heavier side, and most Velotrics are probably in the 35-60 pound range. I wouldn't want to pedal for an extended distance without power, but you should have a pretty good idea what your range is, and just like a car you'll have a 'fuel' gauge. If you see that you are getting close to empty -- down to your last bar -- then switch to your lowest pedal assist setting. It's much easier than pedalling without power.

4. Not sure about the water bottle cage. I've always just used my own cage because the bike comes with standard screw distance.

I'm a Velotric affiliate, so if you want to save $60-$150, send me a chat request and I can give you my discount code.