Well I agree with all of what your expectations and experiences as you state. I too was thrilled when they said 39 lbs. (but it's not) and with the new generation motor and battery, I would have possibly lived with the other negative stuff but now I'm not even sure it's worth selling my Super Commuter and if anything possibly consider the Allant 8+ S for a few pounds more than what I have with my current bike, does that make sense?
I always wanted an additional battery, but I could never justify the cost of $800 to $1,000 or maybe even more with the back rack to install the mounting capability on the Super Commuter 8, as my maximum rides have never been over 50 miles in one day yet (or even to just carry a spare battery) ........but I suffer badly from "range anxiety" being a previous owner of a Ford Focus EV for many years (early adopter). Fortunately, the Super Commuter can be ridden with no power assist with a little effort, unlike other e-bikes I have owned. I've actually rode 18 miles with no power with minimal difficulty (no major hills etc.). With that being said, to spend about $1,000 for the extra battery for the Allant 9.9 if needed might be acceptable if needed, but I don't think I need it nor do I think it keeps the streamlined appearance which is why the bike has an appealing look.
Also, I agree about the fork or some additional suspension, as I approach 70 years old my tired, old bones need as much cushioning as I can get.....
So, will I get a new Allant 9.9 or 8S? I'm uncertain at this point. With all the competition heating up just like in the automotive industry for electric there are surely to be a lot of choices and decisions to consider. However I must say that with the wide network of Trek dealers and their top notch support and customer service that is also a serious contributing factor to think about.
RE: Carbon and absorption negating additional needs for suspension components; I was told that and really couldn't say either way I felt any difference riding the Allant 9.9, albeit for only about 3 miles, hence my desire to try it out for an extended period of time before making any final decisions, especially when compared to the alloy model (Allant 8+S). In the automotive world, you make an EV lighter, it increase range, add a better battery and a better motor, you gain more distance, but in reality other than style, and increased minimal distance, what's it all about?