At this age get him used to the Dremel for tidying his nails. It will help a lot later to keep his nails short so as not to splay his feet. A good looking brindle that should give you lots of fun.
We bought a dremel to do his nails and he absoutely hates it. I let him look, snif and move it while it was not off and he just backs up. I turned it on and he ran away. So we will us the dog clippers for his nails, those seem to be working.
I agree with the others that although he seems to have Basenji in him - his head is def. not Basenji.
As for the leg I'd have it amputated if it troubles him - He'll cope with 3 legs I'm sure, but certainly consult a specialist first. Please keep us updated.
Oh yeah, he looks way more like a b-mix to me than a lot of the pups listed as basenjis on Petfinder. And they mention he's not a barker. What a cutie! Someone go get this guy! :D