I don't think it is odd to bring up possible children, marriages etc for ME3. Not as part of ME3's gameplay, I don't want this to be the sims. But after all these years, I hope when ME3 ends, it is the end, Shepard is retired as a character. I want an end, but not some cheesy lazy wrap up of "everyone dies". I see nothing wrong with multiple ending that show Shep moving on to a command desk job, maybe the orphan Shep background retiring to adopt a bunch of kids. Maybe the renegade Shep taking up Jack on her offer and flying off in a stolen Normandy to explore the galaxy.
Anyways, I hope the ending does show the direction our Sheps go once its over, not simply we win the mission and see some medals being pinned upon our chest.