Alexander because it's my son's name. I also love Ryder because it's such a cool name that you don't here often. I love Elizabeth, but Ellie is not the right nickname for it, and I love Erica.
Aidan and Erica or Elizabeth (Lizzy, Ellie and Eliza) sound very real. It's adorable, practical and would fit for a child as well as later adults. Congrats on the twins! Best
Well for the boy I'd go with Matt or James and for the girl i strongly like Erica.
I don't like Aidan,Ryder,and Sadie.
I also think that the the best combination for twins are James and Elizabeth.
I like Ryder out of the boys list because it sounds really cool, like the name of a rock star. Of the girls I like Ellie, though not Elizabeth.
For the twins, sticking with Ryder for the boy, I'd pick Erica to go with it. Cos I think boy's names are cute for girls, if you add an 'a' at the end. Plus, Ryder and Erica sort of rhyme, so they match.