I do think it is a good idea to think about how you will use the time share now and in the future. It seems like a long way off, but your now toddler will be in school before you know it. We bought our TS when our kids were in elementary school because we loved the idea of having more space when traveling. We still like the extra space, but now that my kids are older, it is getting harder and harder to plan travels in advance, and to even find a week everyone in the family is available. Having time away to reconnect as a family once a year is non-negotiable to me, but planning a year in advance has been difficult. It's easy in theory to say, "This is our family time, it's already planned." But what happens when your kid has been working so hard on their sports team, band, academic team, whatever they participate in, for the whole school year and the team qualifies for the state finals, which just so happens to overlap with your Hawaii week?
In a few more year, that will change again when the kids are out of the house and DH and I have more flexibility to travel on our own. I'm sure we will change the way we travel once again when grandkids come around. Not that a time share has to be a permanent purchase, but there are so many people that seem to buy based on their needs at the moment, and then are desperate to unload it five years down the road when it has become an underutilized financial burden.