Similar names suggestions? Struggling to find 'the one'!

[commsgirl]

Boys: Alistair. Also love Matthew and Alexander but can't use (family names). I like strong, masculine names that aren't too out there and aren't going to date.
Girls: Imogen, Serena. I don't like anything to girly or any of those names that are cute until they're about 10 and then just start to sound a bit silly..

Any suggestions?

*too girly, obviously.

Marianne
Claudia
Nathan

Daniel
Thomas
Ellis

Hannah
Alexandra

Benedict, Rupert, Matthias, Tobias?

Naomi, Nina, Ophelia, Octavia?

Max, Gabriel (Gabe), Rufus, Reuben

Harriet, Claudia

Ahh I love Ellis but rhymes with our surname (or near enough!)

Tobias, Reuben, Max and Harriet are all going on the list!

Marcus

Selina
Thomasin/Tamsin

Joseph
Hugh

Helena
Josephine

James
Aaron
Jacob
Luke
Fergus
Peter
Samuel

Anna
Miranda
Georgina
Stella
Olivia
Natasha
Clara

Leon
Nathaniel
Michael
Adam
Daniel
Christian
David
Gregory
Owen
Robert
William
Zachary

Abigail
Bethan
Megan
Lois
Chloe
Sofia
Cara
Nicole
Catherine
Zarah
Lorna
Esther