I think it's great that you are resisting the commercialism of the season and starting when your child is young. I have 2 stepdaughters, one of whom works hard to get the kids to donate their used toys and so on, and she really wants to have the kids take them to a place where they can learn about the kids who are receiving them. She knows, for confidentiality reasons, that her children cannot meet the recipients, but at least she goes to places where the staff explains about the kids who are needy. She also does this year round, which is really important.
My other stepdaughter is another story - her children rip through their gifts and come up to me for their next gift. The older one is completely bored by family celebrations - he just opens his stuff and heads for the TV. The other one finished so quickly while the other kids (her cousins) were still opening theirs, and she nagged me about why there was nothing else for her. I was very careful to have exactly the same number of gifts for each child, but she was really challenging me and acting ripped off.
My husband and I have a son together, and we were careful to not spoil him all year round. We never did huge birthday parties with 20 kids all giving him gifts - that helped a lot when holidays came around. We also give regularly to food drives and similar things so that giving and being compassionate were always a part of his life. Sometimes we bought something else at the supermarket and dropped it in the food pantry bin at the market, sometimes we contributed to the Scout or letter-carrier drives, sometimes (especially at "off" times like the summer) we made special purchases and went to the food pantry ourselves. We also collected old blankets and towels to give to animal shelters - compassion extends to all living creatures.
Our family celebrates Chanukah, and we usually did one large gift on the last night and then smaller ones the other nights. One night was always a party with friends, during which we lit several menorahs and ate traditional foods, so the celebration was "gift-less" except for goody bags for the guests. Another night was music and family games. Throughout the whole 8 days, we concentrated on the miracle of the original Chanukah and the celebration of religious freedom and diversity, not the gift-giving that is a newer "tradition". A lot of people do similar thing with Christmas.
We also have donated to special promotions done by a local radio station that provides Christmas gifts to kids who have nothing. Our son learned that donating is donating, and it doesn't matter which holiday or religion you donate to, as long as the charity is reputable. Every week before our Sabbath dinner, we put a small amount of money in a "give-away" box - our son always was expected to put a portion of his allowance in there. When he helped us return soda bottles for the 5 cent refund, he donated some of that. A couple of times a year, we emptied out that box, counted and rolls the coins (a good matching and math exercise too!), and determined a way to donate it, either through the cash itself or by buying something to donate.
He also grew up seeing me spend Christmas day in local hospitals as part of a project that gets Jews to perform non-medical jobs so that staff can be home for Christmas. We worked in the kitchen, prepared box lunches for late arrivals, served meals to patients, and so on. My husband stayed home with our son when he was young, but they always did something nice for me like making me breakfast or having a late lunch ready when I got home. So they were part of it.
When our son had his bar mitzvah at 13, he did 13 hours of community service. He chose to collect used sporting goods for needy kids. He contacted a couple of organizations and asked them for a wish list. He then went to local stores with a letter from the rabbi, and many of them gave him money from their community outreach dollars. He used the money to purchase items in their store, and donated them. At his bar mitzvah service, we assembled some of the donated items into arrangements which we used instead of flowers in front of the pulpit, and the rest were used as centerpieces at the luncheon. Instead of guests sitting at table #1 or #5, they were assigned to the "baseball" table or the "soccer table". When it was all over, we took all the donated items to the agency, and he got to meet the people who service those kids. One thing that was nice is that much of this stuff went to group homes for neglected middle school and high school kids, a group that doesn't get much when people donate toys more appropriate for small children.
So, I commend you for starting early with your son. As he grows, you will find new ways to engage him in thinking of others. If you make it part of his life from an early age, you will reap the benefits for many years to come.