Don't underestimate the work required to take care of a large dog with a thick or double coat. It will tax your vacuum cleaner and your patience. Brushing is not optional. The heat of summer can be a serious problems for dogs with lots of thick, long hair.
Having had big dogs most of my life, I've come to understand how likely most are to be prone to hip displacement and serious arthritis. Some sort of certification (if you get a purebred) regarding the hip issue is very important.
For years I'd wanted a Great Dane and thought that breed would be the successor to the Bouvier. I was in my vet's office one day when someone came in with a Great Dane. I was admiring this beautiful dog when I noticed its rump was higher than the receptionist's counter. I asked the dog's age: 9 mos. Later I observed the owner having to lift the dog's rear end into the Jeep they were riding in. I decided that I'd reached and age when lifting a heavy dog would be more of a challenge than when my Bouvier became elderly. In addition, everything costs more for big dogs : meds (based on dog's weight), accessories (collars, leads, car seat or seat belt), boarding fees and FOOD.
Don't know if you're familiar with Bouviers. A fine breed for families... smart, trainable and quite loving, but can be stubborn. Placid personalities and quiet. Tolerant of cats and children. Jack, my Bouvier, (his formal name on his papers was Monsieur Jacques Soniet of Bouchon Kennels) knew many words in English and French, but was never interested in Spanish. He could distinguish the meaning of words in the context of time of day. He learned to take care of business outside on command. He was a great traveler and loved being in the car. People selling door to door were never aggressive or assertive with him standing beside me, silent and large. There's nothing like an intelligent dog to make a great companion. One additional note on big dogs, they tend to have shorter lifespans than smaller ones. Big dogs tend to mature emotionally and physically slower than small dogs. Many bigs are adolescents until 18 mos or longer.
Selecting a suitable dog can be one of the most rewarding commitments you and your family make. I'm looking forward to reading your updates on this process.