I'll add a little info about each name here if it sways your opinion at all or is just nice to know about the name

Hale - I didn't see Hale anywhere in the Social Security Administrations top 1000, so I guess its still unique. If you never find the Haley's I guess, but Haley and Hale still sound different. I think it sounds handsome! According to Nameberry, it means "someone who lives in a hollow", and apparently it has a namesake of Nathan Hale- a revolutionary war hero. So far I see no negatives.. yet hehe. Plus I think Roman and Hale would sound quite fine as siblings. Its my favorite new boy name of late! Feels fresh and different, and its never been on my list previously. How fun?!
Gunther - It hasn't emerged onto the SSA charts either. Its a very German name, meaning "bold warrior". I have fond memories of the name. My dad calls my older brother by it sometimes, just random nick name. He calls him Gunther, he called me Fido for a while (long story), calls me sister Cutie Pie, and my little brother Bear (but its a nick name he's adapted to a while ago). Other, more public, associations are Gunther Grass (a novelist), and there's a gentleman named Gunther in a poem so says Nameberry. Honestly, I feel this as more of a guilty pleasure. But I still am growing increasingly fond of it!
Gunnar - The Scandinavian version of Gunther. Yeah, everyone see's this and thinks all military or violent, but in all technicality its not. (Yet I still acknowledge its going to be seen as a kid with violent parents). May end up another GP. Or a middle name. Apparently Gunnar is on the SSA lists though! Its number 502, with 515 babies receiving the name in 2011. Apparently in Scandinavian legend Gunnar is a key figure, and quite traditional there. They probably don't think weapons when they hear it, but still. I honestly do like it. And I met a Gunnar who just made the name sound so attractive! Cutest little toddler <3
Hamish - okay, off the bat, probably a GP. Pronounced HAY-mish, for those who aren't sure. Its not ham-ish, like ham. lol. I can see how it could possibly give off teasing potential, but do you think it'd be too bad? Is it acceptable? I love the sound of this name, Hay is just so attractive! And the mish is a soft ending, making Hay more complete. That was a totally drawn out way of saying I like the sound haha. The only thing that troubles me even a little is that its the Scottish equivalent of our James. I had an awful experience with a James and I greatly dislike hearing the name at all, and since I saw the relation its been stuck in my head a little. WDYT? Oh, and no its not on the SSA charts hehe.
Hawkin(s) - it makes me think of author Nathaniel Hawthorne lol, even though Hawkins and Hawthorne are distinctly different. Hawkins feels like it'd be an authors name, or someone smarts name. Idk. I am still debating on that S as it almost feels unecessary as I don't care for plural names (ie Collins), but Hawkin itself almost feels... like its really missing the letter. Hawkins feels like such an established last name that it needs the S. WDYT? A website tells me it means "little Hawk", I felt like that was too obvious lol. I like the idea of nick name Hawk though, it sounds manly. Plus I adore nature names, it fits right in! Nature names are pretty in style, as are surname names which would make Hawkins fit in perfectly.
Fisher - Fisher isn't unheard of, its 854 on the SSA charts with 248 babies receiving the name. So it feels a little more plausible than Hawkins. Well established before my idea of use. I love the idea of nick name Fish really though, as I nick named my brother Bear when we were little and it really stuck well. Wouldn't it be cute to have Uncle Bear and Nephew Fish? LOL! I swear I don't only like it for the idea of that happening lol. I think the name sounds handsome <3 I love occupational names so much lately.
Linus - Yeah, a GP for the moment. It isn't on the SSA charts at all, and its stuck with the Peanuts association. But to me, thats all the better! Unpopular, and personally I think the Peanuts are a fine association. I have fond memories of the show. Apparently Linus is a Greek name meaning Flax. Kinda interesting. Yay or Nay? Usable? I'd think especially as a middle name it'd work. And idk why people would use the Peanuts as an excuse not to use it, I think it gives good advertising of the name. On nameberry there are quite a lot of associations actually. I recommend looking at it

Ryker - I had Ryder on my list for a while, Mikes not a fan. And it faded out of my liking. We have Ryan on my list, but my neighbor Ryan is my association to it lately so it feels awkward to have it on the list. He doesn't love Riley, and I'm not loving it either.. but I love Rye names and would love to honor my BFF Rye in a name. I honestly like Ryker. (I liked Rylan for a girl but its WAY to close to Roman. Ryker and Roman cut it close too.. but aren't as similar as Rylan and Roman). Ryker would be a middle name only I think.. though I love the idea of first name with nick name Ryo. Apparently its a German name meaning "rich". My only downfall is the fact that "Rikers Island is infamous New York City jail" as nameberry puts it. Ruin the name?
Theodore - This ones been in my thoughts for a while. Would Roman and Theodore do well as siblings? Ro and Theodore? I don't love Theo or Teddy, though Teddy is growing on me for a small child lately. (I have issues saying Theo alone it seems, though all together in Theodore it comes out fine). I like the idea of TJ as a nick name.. Ro and TJ? Idk, I'd rather use all of Theodore.
Reeve - I'm not sure I like it yet, but another I saw on Nameberry and wanted thoughts and whatnot. A fresher version of Reese. Its an english occupational name, meaning "bailiff". My only concern is the fact that Reese is kinda in the family already, not directly but the sound is there. So would Reeve just be too close? Is it a good name, do you think?
Lol, lots of thoughts and opinions to each name. I should get to bed now... I was just too excited over these names to not post them on here! OMG! And I just came up with... Hale Nicastro! It sounds so educated.. and darn handsome! Eeep!
