Last name decisions

Haylee

So kinda long story but my dad passed away last December and a month after he passed I found out that I was pregnant with his first grandson. I have 3 girls at home and they all have my fiance last name but with my son I'm trying to figure out if I want to hyfonate my dad's last name and my fiance last name cause it's his only grandson and would be the only one to carry the last name since this is my last child. We are also naming our son Gotham David ( which is my dad's name). Some ppl are asking why Gotham and it's because my brother died when I was younger and one of his favorite things was Batman. So I'm trying to figure out what one sounds better Gotham David peterson-ashworth or just Gotham David ashworth.