It makes me think of US folk singer Arlo Guthrie (born in 1947, and Arlo is his original, legal first name). It has become really popular lately in the UK, as have other -o ending names for boys. Which doesn't mean you shouldn't use it, but be aware that it might spike and fall, so you have a lot of little Arlos now and in 30 years people are saying "eeew, what a '20s name!!" 😀
Not sure if you're looking for alternatives, but there are still a few less-popular -o names. I really like Arno, which is both a traditional German-language shortening of Arnold and also the name of an Italian river that runs through Pisa and Florence.