[name_u]Arlo[/name_u] - I like it okay. I had it on my list as a MN to honor my grandma ([name_f]Arlene[/name_f]), but, as far as -o names go, there’s a lot of others I like more ([name_m]Leo[/name_m], [name_m]Hugo[/name_m], [name_u]Bo[/name_u], [name_u]Theo[/name_u], [name_m]Cayo[/name_m]/[name_m]Caio[/name_m], [name_m]Maximo[/name_m], [name_m]Otto[/name_m], [name_m]Augusto[/name_m], [name_m]Nemo[/name_m], [name_m]Cosimo[/name_m], [name_m]Laszlo[/name_m], [name_u]Cato[/name_u], [name_u]Rio[/name_u], etc.). Still a nice name, though, and I came across [name_f]Emilia[/name_f] and [name_u]Arlo[/name_u] as siblings a while back, and that made me really love [name_u]Arlo[/name_u] for a while, because I thought that was just perfection!
[name_m]Benjamin[/name_m] - I like it a lot! It’s my little second cousin’s name, and I love him. For a while there, it was my top name for a boy, but that was probably over 5 years ago. I still love [name_m]Benjamin[/name_m], and [name_m]Ben[/name_m], and it’s a MN on my list.
[name_u]Cruz[/name_u] - not really my thing. It seems too surnamey to me. I like that it means “cross”, though.
[name_m]Damian[/name_m] - I like it. It seems very cultured and educated to me, and I don’t think of horror movies at all. 
Except to try to convince parents to use it, because I so want to meet an adorable little [name_m]Damian[/name_m]! I went to high school with one, and he was very friendly and outgoing and artistic.
[name_m]Dominic[/name_m] - love it a lot, and the nn [name_m]Dom[/name_m]!
[name_u]Elliot[/name_u] - I like it, but love other -et names more (like [name_u]Everett[/name_u]!).
[name_m]Ezra[/name_m] - I like it a lot. It’s currently a MN on my list.
[name_m]Gabriel[/name_m] - I’ve really been swooning over [name_m]Gabriel[/name_m] as a MN lately, but I don’t know what to pair it with. 
Hopefully I’ll get it on my list soon.
[name_m]Graham[/name_m] - I like it okay, but prefer [name_m]Grant[/name_m] vastly.
[name_m]Griffin[/name_m] - not a huge fan. I liked it probably 20 years ago, when I was in elementary school, and had a [name_m]Griffin[/name_m] for a classmate. I think I thought it was cool when it was still obscure, but now everybody likes [name_m]Griffin[/name_m], and I’m just tired of it.
[name_m]Jasper[/name_m] - okay, but I can’t really imagine a little boy named [name_m]Jasper[/name_m]. I like [name_m]Casper[/name_m] much, much more. Or even [name_m]Gaspard[/name_m].
[name_m]Leo[/name_m] - love! [name_m]Leo[/name_m]'s on my top 10.
[name_u]Luca[/name_u] - I like it okay, but prefer [name_m]Lucas[/name_m]/[name_m]Lukas[/name_m], or even [name_m]Lucian[/name_m].
[name_m]Lucas[/name_m] - love, obviously! I seriously considered adding it to my list a while back, but it didn’t make the cut.
[name_m]Mateo[/name_m] - I grew to like it because I sponsor a little girl in [name_u]Peru[/name_u], and the name of her hometown is San [name_m]Mateo[/name_m]. I like that it reminds me of her. As for international [name_m]Matthew[/name_m] variants, though, I prefer [name_m]Matthew[/name_m], [name_m]Mathieu[/name_m], [name_m]Matias[/name_m], [name_m]Matthias[/name_m] (!!!), and Matheus to [name_m]Mateo[/name_m]/[name_m]Matteo[/name_m], though. Still a nice name, though, and [name_m]Matt/name_m and [name_m]Teo[/name_m] are cute nns.
[name_m]Miles[/name_m] - I like it as a MN, but I’m not too fond of it as a FN.
[name_m]Milo[/name_m] - used to prefer it to [name_m]Miles[/name_m], but now I like [name_m]Miles[/name_m] much, much more.
[name_m]Nathaniel[/name_m] - I like it a lot! It’s a MN on my list, but I’ve considered it as a FN, too, because I love [name_m]Nate[/name_m].
[name_m]Nicolas[/name_m] - it’s okay. With this spelling, I want to say it the [name_m]French[/name_m] way (nee-koh-lah), and I like the more English [name_m]Nicholas[/name_m] better, or even just the [name_m]German[/name_m] [name_m]Klaus[/name_m]!
[name_m]Oliver[/name_m] - it’s okay. I like [name_m]Oscar[/name_m] and [name_f]Olivia[/name_f] more, though.
[name_m]Ronan[/name_m] - love! I slightly prefer [name_u]Rory[/name_u] and [name_u]Rowan[/name_u], but I love [name_m]Ronan[/name_m] a lot, too.
[name_u]Rowan[/name_u] - obviously, love! He’s in my top six. I would lovelovelove to have a little [name_u]Rowan[/name_u] one day!
[name_m]Sebastian[/name_m] - love a lot! He almost made it to my list as a FN, and I currently have him as a MN for [name_u]Rory[/name_u] (and maybe [name_m]Jack[/name_m], too).
Overall, great list! I love a lot of these names. My favorites are probably [name_m]Benjamin[/name_m], [name_m]Dominic[/name_m], [name_m]Ezra[/name_m], [name_m]Gabriel[/name_m], [name_m]Leo[/name_m], [name_m]Lucas[/name_m], [name_m]Nathaniel[/name_m], [name_u]Rowan[/name_u], and [name_m]Sebastian[/name_m].
Good luck!