I can't really vouch for them in carrying any kind of weight, but since you keep mentioning the wide toebox, look at the Keen Voyaguers.
Before I had the surgery for Morton's Nueroma, I couldn't wear anything that was even slightly tight, these worked. I've worn the Voyaguers hiking a couple times and they were as good as any other boot for it (Keen has been known to have quality problems though although I haven't had any issues).
Good thing is Keen gives a 50% off military discount. If you search Keen Voyaguer on LF you'll get some more info.
That being said, when I did do some rucking I used a non goretex version of the Vasque Breeze myself and they were great boots especially in hot weather (TX 95+ days, high humidity). These were the original model of the Breeze, I don't know how the Breeze 2.0 is since I still can't wear anything even remotely pointy.