It's a tough decision.
When I named DS#1, I was 14 (didn't have him until 26). It was a name in a favorite book at the time and it just stuck. DH liked it, luckily. It was really the only time we ever agreed on a name.
When DS#2 was born, we couldn't agree. We ended up letting DS#1 name him since he was the only one with any definite opinions. Shhh, it's my favorite name of all.
When DS#3 was born, we still didn't have a name. And they wanted one immediately as they were whisking him away to NICU. I just said a name, it was one I liked and always made it to the short list, but always rejected. Somehow I figured this might be my last chance and since it always came up... DH just went with it. With all that was going on, I don't think he would have dared said anything no matter what I said. Regardless, it just fits him. I think it was rejected just to wait for him--and he is soooo different looking from our other kids.
Perhaps just waiting until he's born might make the decision easier on you. One will fit or not. Anyhow, I went with Callum. DS#1 has had a different Gabriel in his class for the last 3 years & we have two neighbor kids named Gabriel. I like names that are a little different.