Two is perfect right now.
Adding more dogs to the family is something that we discuss a lot around here. With both my daughters having their own dogs now; one of us is often contemplating an addition. I have many opinions on the subject and the older I get, those opinions shift slightly and new ones develop. Opinions change from experience' experience is a wonderful thing and it only comes with age. Having lived through so many things you can somehow see much clearer than when you are young. When I was young, in my teens and early twenties I was very impulsive. I would act before ever considering, making rash decisions. Luckily that changed along the way.
Elsa is the most recent addition to our family; Penny in Nicole's home and Luna in Jamie's. It took a very long time to find the right breeder and the right dog for us. With 3 seniors in the house already there was much to think about. The dog had to mesh with the others; she had to be patient, kind and understanding. Elsa was all those and then some. But it didn't happen by chance, Elsa's breeder knew what we wanted and chose her for us. But along with adding the right dog is knowing the right time to add. There are many things to consider with regards to timing when you want to add another.
How old is the youngest dog that you have already? Are they old enough to have something to offer a puppy? Adding another dog before your other one can offer life experience can just add up to tons of work. Many folks add another dog just to keep their existing dog company. Although a great thought, it doesn't always work out. Two young dogs are twice the work. The first dog may not have had their fair share of "one on one" time. Time to develop, learn and grow into a fully adapted and mature dog.
Do you have time to dedicate to a puppy? Real time? I would love a puppy right now. In fact we had planned for one; but things change, life unfolds without giving us a heads up. So right now is not a good time to add a puppy to our home. But I am hoping that the next year will bring with it a new family member for us to love. I also want to give Elsa another year of "her time." Our bond has become an intense one. She gets lots of time to play with friends and she has Luke of course. They play almost every day and it has taught her to play gently when needed. There is much more to life than constant brawling with a young playmate.
I am not an advocate of buying two puppies at the same time, for many reasons. Time spent with your dog is all about quality, not quantity. Same goes for spending time with other dogs. Having to teach two dogs simultaneously is a boatload of work. Why not let your dog help; by waiting until they have something to offer? When we add another puppy to the family, Elsa will have lots to teach it. She will have three years of experience to offer the new blank slate. Three years to me is the best time; that is unless there are other circumstances that need to push it up or back.
This is of course, my opinion.