I think Cain sounds like a strong name. I like its length, its meaning and the fact that it could easily suit a variety of personalities. I'll admit that the biblical association is pretty dark, but that doesn't have to affect the name as a whole. It's not like the biblical Cain is the only Cain that every existed. There are plenty of kind, goodhearted Cains; and, in contrast, there are many bad people who share names with honorable biblical figures. And there are several people who are not named Cain that have killed their brothers. That's proof that a name does not determine an individual's personality. Overall, I think Cain is a cool name with a unique vibe. And if your name is Cain, don't let anyone tear you down because of one negative Cain that lived some 2,000 years ago. Prove them wrong and show them that there are plenty of good Cains out there.
Sorry this name is awful. Even if you don't think about the Biblical (which are kind of important, seeing as that's where the name originates), it sounds like the name of a pro wrestler... or an old man's cane that he might use to whack little, obnoxious children. If you want a name like Cain, just go with Kane, which sounds the same but has a completely different meaning.
I think Cain is a cool, sexy and suave name to use on a boy. Most people, like me, don't really associate names with the bible unless it's something like Jesus.
Cain gives people a pretty bad impression. Otherwise, it's a nice name. I think God created more people after he made Adam and Eve, but I'm not sure (obviously).