I quite like the meaning behind [name_m]Invictus[/name_m], and I do genuinely love unusual and powerful names. And I understand that the name means a lot to you. I also have some names I am attached to. But I do feel like [name_m]Invictus[/name_m] would be a lot stronger as a middle name.
A name can be beautiful, but I’d think if it still feels like a good name when you imagine a five-year-old, a teenager, or a grown adult introducting himself as [name_m]Invictus[/name_m]. A five-year-old [name_m]Invictus[/name_m] being introduced in Kindergarten. A teen boy being called [name_m]Invictus[/name_m] during attendance. [name_m]Other[/name_m] boys reacting to it. I don’t think a kid could really appreciate the name. [name_m]Not[/name_m] because unusual names are bad, but because a child has to actually live with it rather than the name just being cool on a list.
Maybe something with a similar sound or meaning without being so grandiose? Or maybe use it as a middle name. That way, you can call him [name_m]Invictus[/name_m] in everyday life, but he’ll get more of a choice. If he wants to be called [name_m]Invictus[/name_m], he can introduce himself as such, or ask to be called by his middle name during attendance. It’s easier to have a slightly more neutral first name with the flexibility of a powerful middle name than have a highly unusual first name. In the first situation, asking to be called your middle name wouldn’t be embarrassment, but rather a feeling of pride over your name.