[name_m]Greyson[/name_m] is my favorite with your sibset. I would usually lean toward [name_m]Clark[/name_m], but I don’t think that would sound as good with a one-syllable last name.
[name_m]Greyson[/name_m] would be my choice but I would probably use the [name_m]Grayson[/name_m] spelling either way its a lovely name and flows well with the siblings.
I like [name_m]Grayson[/name_m] the best, but the nickname [name_u]Ren[/name_u]/[name_u]Wren[/name_u] for [name_m]Warren[/name_m] might tip the scales for me. [name_m]Clark[/name_m] is nice too but sounds somewhat similar to [name_u]Brooke[/name_u].
I think [name_m]Greyson[/name_m] is overused, I love [name_m]Clark[/name_m] but not sure if it would sound good if your last name was [name_m]Young[/name_m].
[name_m]Clark[/name_m] followed by [name_m]Warren[/name_m]. [name_m]Grayson[/name_m] is way too overused for me. [name_m]Clark[/name_m] is so simple yet awesome.