I like Miriam and Jonas. Are you still favoring the nn Mim?
Hmm... other names that fit the style... I don't think Conrad and Alice are far off the mark at all, personally, but let's see...
Miriam, Jonas, & Fern
Miriam, Jonas, & Helen
Miriam, Jonas, & Sadie
Miriam, Jonas, & Eloise
Miriam, Jonas, & Annora
Miriam, Jonas, & Edwina (I prefer the ed-WEE-na pr. myself, but it's also said ed-WIN-ah)
Miriam, Jonas, & Marjorie (I know, just as bad -- dreaded M theme. But you could use the nn Jorie? Wait... Jonas, Jorie... umm...)
Miriam, Jonas, & Leona
Miriam, Jonas, & Liora
Miriam, Jonas, & Amabel
Miriam, Jonas, & Arabella
Miriam, Jonas, & Verona
Miriam, Jonas, & Hazel
Miriam, Jonas, & Imelda
Miriam, Jonas, & Roma
Miriam, Jonas, & Harold
Miriam, Jonas, & Arthur
Miriam, Jonas, & Clarence
Miriam, Jonas, & Clyde
Miriam, Jonas, & Blake
Miriam, Jonas, & Victor (but you'd have to call him Vic, because how noir is Vic?)
Miriam, Jonas, & Phillip
Miriam, Jonas, & Leo
Miriam, Jonas, & Noble
Miriam, Jonas, & Lucien
Miriam, Jonas, & Pascal
Miriam, Jonas, & Duncan
Miriam, Jonas, & Anton
Miriam, Jonas, & Kurt
Miriam, Jonas, & Bertram
~ Arcadia ~