The standard says:
Legs straight with clean, fine bone, long forearm, and well-defined sinews
So would the thicker bone be a fault over one that had finer bone (more refined looking, not fragile looking bone).
I'm also curious about front leg bones that are more bladed - is that something that runs in specific lines and is that considered a negative or a positive?
All basenjis should have a bladed front leg bone. The degree may look different with the dogs build, IMO, but the concept is the same.
And as far as thicker bone being a fault, depends on your view of the standard. I would prefer a more substantial bone in both Bitches and Dogs. And there is a difference between "good" bone and a dog/bitches being too much bone. There is a difference between good/substantial bone and being coarse…. which I have seen in several different lines that you have what I consider a "wonder" puppy that by the time he/she is 5 or 6 they have developed into a very coarse dog.
What I like to see #1 is that if I look at a bitch, I know it is a bitch without having to look to see what the sex is, same for dogs.
If you go to my website, Maggii is a bitch that you have no doubt that she is a bitch, but she had substantial bone (another one is Crystal), on the other side of the coin, Mickii and Kristii has less bone and substance if you compare the 4 bitches.
And in the ring it comes to the judges preference, some people believe that substantial bone is "fine" boned, others do not. Not always black and white.