Well, of course I don't know where you live, but I personally would only use the following as first names:
Abram (or just Bram?)
Arlo (I love Arlo, but my mother told me it sounds like the noise a whale makes...it's kind of lost the appeal for me now, but I definitely want someone else to use it)
But I would consider these as middle names:
The others aren't really my style, but I think practically anything goes in the middle so...good luck!
Abraxas- hmm, it is out there but, I LIKE it. I'm sure if it's useable, however.
Luciano- I could see both sides of this. People are starting to gravitate toward softer boys names, so Luciano could fit right in. On the other hand, he may be too unheard of.
Macario (ma KAR ee oh)- Easy to pronounce and spell. Yes, I think this is useable, although it would work best if you are of Hispanic descent.
Marco- Useable. I know a Marcos, so why not Marco?
Calder- I think that with the more frequent surnames-used-as-first-names and ending-in-er names Calder would work well.
Abram- Yes, useable in my opinion.
Amadeus- I love this and think it would be adorable on a little boy. It would work best if you are a fan of the composer, I think.
Nazario- I don't think the world is ready for this one yet.
Arlo- Useable, older boys names are roaring back into use!
Gage- I like it. Shorter boys names and names in general are on the rise. I think it would fit right in with all the Jacks and Mays.
Bronx- Mmm....I don't know. I think you would always get a lot of comments on this name.
Dashiell- I've seen this popping up more and more on the message boards and, though I'm not a fan, I believe it to be useable.
Lastly, I'd say go for whichever name you love, despite other's opinions!
I think they're all usable, if you love the name go for it!
In my opinion Marco, Calder, Amadeus, Bronx and Dashiell are usable. Luciano is usable if you're Italian, Macario if you're Hispanic. Arlo would be a cute nickname for Alfred or something else but doesn't stand alone. Gage just makes me think of the textbook company or a temperature gauge. Abraxas and Nazario are a bit too much for me.
Abraxas - I like it. May get comments but usable IMO
Marco - Usable
Calder - Love it! Very usable.
Abram - Love it! Bram is cool too!
Amadeus - People use Wolfgang so why not Amadeus, but I think of the composer
Arlo - Love this name too!
Gage - Perfectly usable, but it always looks misspelled to me.
Bronx - IMO, no - Very trendy
Dashiell - This one is growing on me. Usable
I did some thinking about these names since there seems to be an "ethnic" reaction to these. I see people using Nordic names, Greek names, French names, all sorts of names used by all sorts of people. Why not use these perfectly good names if you like them. Why would I even separate them from Marco, which seems perfectly usable by anyone.
Luciano - Good name
Macario (ma KAR ee oh) - I like this, though I never heard it before. nn Mac, Cary?
Nazario - The z sound is cool but it seems like Noel/Noelle to me - a "seasonal" name
Abraxas - no. looks made up.
Luciano - ok
Macario (ma KAR ee oh) - ok
Marco - definitely
Calder - yes
Abram - yes
Amadeus - yes
Nazario - no
Arlo - definitely
Gage - yes
Bronx - yes
Dashiell - yes
I'ld pick Dashiell or Luciano if you want to stand out
Arlo or Gage if you want to blend in
I like weird names so most of these are completely usable in my book
Abraxas- I had to google because it seemed familiar but I wasn't sure why. It's the name a Santana album! I love Santana plus apparently "the 7 letters spelling its name represent each of the 7 classic planets—Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn" so I'm really liking it. Brax is a cute nn
Calder- I like it because it reminds me of caldera. There's also a race track here called Calder
Nazario- not a fan but Navarro is a family name
These are normal to me