Hello! I am the mama of two boys [name_u]Aiden[/name_u] [name_u]Michael[/name_u] (10) and [name_m]Ethan[/name_m] [name_m]Ryland[/name_m] (8). I’m expecting our third child - a total surprise - and she is a little girl. My husband is fairly opinionated when it comes to names so making our list has taken a little bit of time! I’d love for you to critique and give us your opinions on our list to hopefully help us narrow it down. Her middle name is going to be [name_f]Marie[/name_f] and our last name is [name_u]Porter[/name_u]. 
[name_f]Haleigh[/name_f]
[name_u]Skylar[/name_u]
[name_u]Peyton[/name_u]
[name_u]Mackenzie[/name_u]
[name_u]Reagan[/name_u]
I vote for [name_f]Haleigh[/name_f] or [name_u]Reagan[/name_u] 
Congratulations!
From your list, I do not like [name_u]Peyton[/name_u] for you because it is very similar to [name_u]Aiden[/name_u]. (I’m picturing both kids turning around when you shout one of their names from across the room…not that that’s a bad thing.) For a similar reason, I would choose [name_u]Skylar[/name_u] over [name_f]Haleigh[/name_f] and [name_u]Reagan[/name_u] so that all your kids’ names would have a different primary vowel sound, making them more distinct.
Purely on style, I like [name_u]Skylar[/name_u] and [name_f]Haleigh[/name_f]. Both sound lovely with [name_f]Marie[/name_f]. I also like the idea of your little girl not having an -n name—it sets her apart while giving the brothers their own connection.
1st choice: [name_u]Aiden[/name_u], [name_m]Ethan[/name_m], and [name_f]Haleigh[/name_f]
2nd choice: [name_u]Aiden[/name_u]. [name_m]Ethan[/name_m], and [name_u]Peyton[/name_u]
[name_f]Haleigh[/name_f] is my pick!
I like [name_f]Haleigh[/name_f] the most, [name_u]Aiden[/name_u], [name_m]Ethan[/name_m] and [name_f]Haleigh[/name_f] makes a good sibset together and it suits the middle name you chose too. Congrats
I like [name_u]Skylar[/name_u] the best. [name_u]Aiden[/name_u], [name_m]Ethan[/name_m], and [name_u]Skylar[/name_u] sound lovely together.
I like [name_u]Haley[/name_u] and [name_f]Hailey[/name_f], but not wild about [name_f]Haleigh[/name_f].
[name_f]Haleigh[/name_f] [name_f]Marie[/name_f] [name_u]Porter[/name_u] is so cute!
Honestly, none of these names float my boat. I would use another modern/classic like your son’s.
[name_f]Audrey[/name_f]
[name_f]Violet[/name_f]
[name_f]Caroline[/name_f]
[name_f]Kate[/name_f]
[name_f]Abigail[/name_f]
[name_f]Lucy[/name_f]
[name_f]Lila[/name_f]
Based on your list, how about:
[name_f]Hallie[/name_f]
[name_f]Phoebe[/name_f]
[name_f]Stella[/name_f]
[name_f]Mila[/name_f]
[name_u]Peyton[/name_u] and [name_u]Reagan[/name_u] get my vote because they fit with the sibset N ending sound.
I like [name_u]Reagan[/name_u] best from your list.
I like [name_f]Hayley[/name_f] but just hard to find the appeal of other spellings.
I agree with pp boyandgirl that the modern classics she suggested would work better with your boy’s names.