There’s negligible advantage in loss going from pl259 to N connectors on HF. You don’t have the kind of losses you do on VHF and especially UHF. The only time N is really nice is when you need an intrinsically weatherproof connector -but this is mounted inside the weatherproof box.
If you want slightly better loss specs AND a more convenient, quicker connector, BNC is great. But PL259, as I said, is fine.