For starters, you're talking about a pretty specialized bike, and assuming it's going to satisfy anyone that see's it. WRONG! It's WAY over the top for many riders. Why would anyone want to drag around the extra weight of that battery and suspension if all you're doing is commuting 5 miles to work and back on paved roads? Or lug it up a flight of stairs to your apartment?
Another "for instance", because I live in a hilly area, my perfect bike would be based on a GMAC rear hub for the awesome regen afforded by that setup. I have NO interest in a mid drive - for a FEW reasons that are way off topic here! Open a new subject and I'll be happy to engage you on the topic.
Second, just as you say all home builts aren't a big pile of crap (with cables and wires hanging out everywhere), If you had an open mind on the topic, pretty sure you would see over the counter stuff that would be as impressive as anything you can build!
Bottom line, though you do describe a set of specifications that will appeal to some, it has features FAR from the universal appeal you allude to. -Al
"For Starters", "Another", and Bottom line"... wow. Did you read the basic statement?
"Find the perfect bike for you and hang a BBSHD or 02 on it. Fat bike, hard-tail, MTB, tour-bike, cruiser, even antiques." I don't assume anything. If you want a bike you can carry back to the car after
a whole 10 miles ride... fine. I didn't want to collect bikes like shoes, one for this, one for that, a fast bike, a comfortable bike, and on and on. An ebike that you commute (rather than walk) 5 miles a day can also be ridden 75 miles on a long warm day when and IF you actually "do it" rather than just argue about "how you would do it". Also, I can walk my bike up-stairs pretty easily with the motor but I understand the point.
This is a good one... you want a light bike and one that does regen? Hummmmmmmmmmm, not gonna happen, at least not well. Regen capability has to have (significant) weight for gravity to pull it downhill to capture even 5 to 10%. Why do you want regen if you only ride short distances?
My mind is "open" except on Lima beans I hate those nasty little things. I hate to point this out but bikes have had cables and wires "hanging out everywhere" ever since hand brakes and gears were added. Not sure how that affects the ride, you know... since that's what bikes are for. I enjoyed women from the 70s more than a woman from the 2000s... if you see what I'm getting at.
The real "bottom line" here is that you brought up your tern "universal appeal" not me. I said you can build a better ebike than you can buy and I stick by that. Especially when the owner/builder can get over the hump in understanding how much better a mid-drive is than a converted washing machine motor. My
set of specifications is exactly that, mine. Most people don't spend the time on their bike(s) or use it/them in the way I do. Do you need a Speed-hub to ride to work, nope, but once you have one you don't want to go back, like cooking on a stove daily rather than over a fire.
The problem is that 90% of ebike riders have no idea what they want at 1st and are missing the target when they buy the lowest end (cheapest) ebike they can find. Production ebikes are built to sell more than they are built to ride. I like the feel of cut crystal in my hand, single malt tastes better when you drink it out of a cut crystal glass and I wouldn't drink it out of a paper cup... others would.
The specs I mentioned were mid-drive, big battery, the best charger (Grin Satiator) and a input control.
If anyone would have been building an ebike that can do what mine does I would have considered it... no one was or is to this day.