We went through the same situation, and chose a Leonberger. Harley is now 9 months old, and the most wonderful dog you could ever wish for.
We have 3 children, 7, 9 and 15, but all our neighbours have little ones and we get daily comments on how wonderful Harley is. He is gentle, more gentle than any other dog I've met.
He is apx.90 lbs now, his dad was 160, and mom 130, so he's still growing, food and vet bills are high, but worth every penny to us. Also, Leonbergers are expensive to buy from a good breeder, just another thought. They DO shed, but we groom him weekly, and "furminate" frequently. They do require alot of love. THey are constatnly by your side, even in the bathroom. They lean on you, often called "lean on bergers". THey talk, wookie talk, which is sooooo funny to get a full conversation out of him. And they do not like being alone, Harley has ever only been left for a couple hours in the crate.
It was difficult to find a vet familier with the breed, so our vet relies on advice from our breeder.
To give you an idea of their rareity, there are 18000 Labradoodles in Ontario and 300 Leonbergers. You will be asked everyday what kind of dog he is, and everyone loves them!
I love Newfs, and may consider one if we ever add to the family, but had to come to the realistic decision, that I hate drool!
Leo's have similar personalities, and in fact there is a Newf pup in our neighbourhood who is more energetic than Harley! He gets walked 2 20 min walks daily, with a few trips to the dog park during the week.
The biggest problem we have at the dog park is that some dogs are intiminated by his size and go at him, and he's so sweet that he gets terrified of them, it's pretty funny actually, lol...
My vote is Leonberger!