Family of 3..... maybe 4?

I've gone back in forth in my own thoughts pretty much everyday about whether or not to give "Bug" a sibling. On one side he will always have a playmate, someone to talk to and someone to look up to him. But on the other hand what if they never get along, I won't be able to put as much into getting him into the school of his dreams because we have to make sure we don't push one and not the sibling. Time split, making sure everything is even and so on. Sounds selfish but this is seriously what goes through this crazy head! I'm already 31 and have always said once I hit 36, we're done for sure. So truthfully I have 5 years to think, BUT I also don't want more than a 3-4 year age gap..... Does anyone else do this to themselves?! I really would love some honest, truthful, straight forward opinions on 1 vs 2 kids. BUT I can say we will have no more than 2!