My nephew's a Lachlan - love it, but for people who don't understand the Scots "ch", it does run the risk of being pronounced something like LACK-lan or LOCK-lan (or even LACK-linn/LOCK-linn). (I'd give the woman in the video my chips if she asked, but the real life pronunciation is quite a bit softer!)
I like Adrian, despite Mole - have Hadrian on my list.
I also like Keir (or even Keith, or Leith) better than Kerr, and love Jax as a nickname: maybe for Jackson, Jason, James, or even Jonathan.
I like Wren, Sien(n)a, and Isla from your girls' list.
Some other possibles (apologies for duplicates from PP):
B: Adair, Anselm, Ciaran/Kieran, Cillian/Kilian, Cormac, Ewan, Justin, Ringan, Stellan, Tristan
G: Alison, Blair, Blythe, Eilidh, Elin, Erin, Esme, Geneva, Ginevra, Greer, Honor, Liadan, Mirren, Morven, Paige, Seren
Either: Arran, Avery, Blake, Lennox, Morgan, Robin, Sage, Teagan