Thanks all. d8veh - I don't quite follow that logic, in as much that I can take any bike, including an electric, for general maintenance to a local shop.
Whoosh - I'm hovering around 14st, a little over at the moment, hopefully soon to be a little under. Although the hill I was able to try on the Alamo was considerably less severe than the worst of the local ones, it wasn't insignificant and would normally require a fair amount of work, and it felt extremely easy with the motor. Superficially, the picture you posted looks different to the Alamo, there's some external components I don't see on their hub drive, but I could be misinterpreting. It sounds like I'm borderline between your motors, but is there another road-centric bike that you make that has the SWX02?
Danidl - the modified regular bike I use (bought for the staggering price a decade ago, new, of £88), isn't far off what I'm looking for, except electric. It's gearing is good both for steep uphills and powering on the straights / slight downhills. It has the most roadworthy tyres with little tread I could get, and it has bar ends. I've never gotten used to drop handlebars and that different riding position, and don't like the thought of cleats. So in other words - something at the road-end of a hybrid, as light as possible, is my dream bike.
The Alamo is about 19kg, which is - as you say - pretty much on the light side, and vastly preferable to me to many of the alternatives which could be anywhere between 25-30kg. Those bikes, it seems to me, are designed purely for electric power and not for any manual intervention, which isn't what I want. This possible Boardman / Brighton mod would be more like 17kg by my maths, another step in the right direction, but it might not be possible to evaluate how it will turn out. On the Alamo, I was able on favourable terrain / wind to be able to pedal fairly comfortably at 19-20mph, and surely a lot of the reason why is that the weight isn't too horrendous, along with the road tyres and gearing.
Will be very interested to hear more thoughts on the Bosch system. Indeed, an idea of a comparison between Bafang hub, Bafang mid position and the Bosch would be worth its weight in gold.