If you like
Walter you like
Walter, go with your gut girl.
I personally prefer
Sullivan and
Oskar before
Walter but it's your baby. Since you are down to 3 it also might be fair to wait until he is born and "see" which one of the 3 he most seems to be on arrival. Ik several of my RL friends are major advocates for not even considering names until they are pregnant because there is no way to know who they seem to be until they exist.
Go with your instincts on the situation.
Please rate my "Names I would Use" list & "Backup Favorites" list. Feel free to rate some of my other lists too if you have the time.
https://www.behindthename.com/pnl/223226/138473