I'm generally in the no neuter side with males. With bitches it's different and breed specific. They have research proving that not spaying has significant impact on diabetes in Samoyeds. As it is a breed with 12x the rate of diabetes as mixed breeds and 7+ to other purebreds, I would spay a female Sammy in a heartbeat. But a Basenji mix?
If you routinely check mammary glands for lumps and catch it early, mammary cancer isn't a biggie. Plus, she's probably already had two heats so spay or not, risks are the same.
But pyometra? You often have no indication until it's life-threatening. I would, personally, choose to spay by two.
I don't think anyone can tell you what is best. Just don't let anyone bully you either way.