It may just be me, but in reviewing all of the pictures that you posted, your tow/foot appears to be hitting all of the horses that you are sitting, at their elbows. So, unless the horse you select in 16+ hands with a good sized barrel, I believe you are still going to have the same leg length on all of them.
I don't think you look overly large/tall on your mare, but if your height/leg length is causing you to feel uncomfortable (your appearance to others) then I would purchase another horse.
And as to whether our animals love us or have feelings of affection for us as opposed to here comes the food source, I have to go with that my animals geniunely love me. Because there have bee many a time my jumper could have allowed me to continue my free fall over her head and she threw her head up to catch me on her neck and I don't believe she was thinking, "crap if I let her fall who will feed me?"