I think for your height and weight I'd go with the slanted bed/recliner seat rather than the true lie flats which I find to be not very wide and probably not long enough for you either. I'm a few cm's shorter than you and about 35kg lighter and find the true lie fats very comfy but a bit confining both lengthwise and widthwise. I'd think it would be very confining for you.

Therefore I'd recommend going with AA or UA on the 777 out of ORD. Both offer plenty of width and AA has the slanted bed and UA has the recliner which will offer you ample legroom and comfort. If you do want a true flat bed the best available on your routing would be Air Canada thru Toronto or Vancouver but I'm afraid these would be confining. Avoid the Chinese carriers.