I assume males would also fit in cb70 until around 3, depending on the individual.
Yeah a 4x2x2 would be perfect for males! I have my 3.5 year old female in that size right now, and she's about 5 and a half feet in length. She might outgrow it maybe 2~3 years down the line lol. If you want to buy just one enclosure size for a female and be safe, I'd get 5x2 or even 6x2.