Judy, we love Vancouver Island. Until very recently, we lived in the country in the northern midwest, and our life was very outdoorsy. We had a long road trip to BC 2 summers ago with the kids, and my boys LOVED the place, both the outdoors and the city.
* Bosch is a closed system: Bosch sells ALL the parts integrating together, and does not allow integrators to take some Bosch parts and use them with other parts from other OEMs. They also don't allow people to open and repair their assemblies: it all has to be done by them. More or less everything electric but the bike must be Bosch. Most other companies will agree to sell you a motor or a display etc. and let you put them together the way you want.
* Ariel quality: I have read really good things about the company. I am thinking that, if it is true that the Dapu mid-drive has more reliability problems, they may have got caught by it too without wanting to. But, again, I don't have personal experience with this, so I am just concerned about the issue. I was going to call Ariel and talk to them directly to ask more questions. But I have also read that there were significant customer support problems last year. Possibly it got solved, though (see the Ariel subforum here).
* aluminum vs carbon frames: I may not be the best person to ask because I am somewhat prejudiced against carbon (although I used to build carbon racing sailboats...). I have 4 LeMond Poprad 853 moly frames, because I dislike the fact that carbon can shatter in some conditions. I have seen quite a few carbon forks fail. For ebikes, the motor torque is 3 to 5 times higher than a regular cyclist on an MTB for instance, and I know it puts quite a bit of stress on the drivetrain, particularly mid-drives. Carbon is very stiff (you want that) but also more susceptible to shatter. Aluminum is more ductile and less likely to break (although I just read on reddit a guy who had his moped-like frame break on him, I think it was aluminum..). So, in the general case, when you look at good quality frames, you would expect carbon to be stiffer but also more susceptible to catastrophic failure, I think. In the low-end frames, I know a lot of really trashy aluminum frames
On the other hand, as an ex-triathlete, you are probably not putting a lot of stress on those frames: so possibly it is not too much of an issue for you? For me, I would pick aluminum rather than carbon but I mass a lot more than you.
* [Edit: forgot to discuss eProdigy] I think you need to look at all that was published on this system, in particular by unbiased third parties, and find out if someone ever discussed it. Possibly you can call the company and ask directly? I am pretty sure they did not design a motor from scratch. You may also want to see what users say about their bikes, but, if possible, not on the company web site, because too often they just discard bad reviews on their own sites. I'd love to know what you find out.
Hope this is clear
It is, to a degree, a matter of opinion, and some may disagree with me.