Hello

I am in the process of planning up my first e-Bike build using a LHT frame set, with 26” wheels, and am wondering if the bionx frame mounted battery would fit on the third attachment point?

As a heavier rider at 290, give or take a pint of ice cream or two, I am concerned about the power of the bionx system with the 350 motor sizes, and their battery power with about 500 pounds of man, canine, and steel moving around Portland, with the desire to climb some of the better summits for photography with my canine.
Bionx is the only brand that my LBS can order, so it adds small comfort since it would be there head ache if a mishap occurs. As they always say, you get what you pay for, and security is expensive.
On the other hand

It looks like there are more powerful units (48v 1000w) motors and Batteries on Ebay, but I also understand the risk associated with this route if something were to not work out.
I do want a system that has the capacity to have peddled assist for when I am commuting, but can throttle like a scooter on down days with my health, and be in the middle when I have Wally. Comfort and reliability are more important than just out right speed.
Just looking for other perspectives, and to see how much I am over thinking this.