I think my favorite would be either [name_f]Caitlyn[/name_f] or [name_f]Kaitlyn[/name_f], with the original [name_f]Caitlin[/name_f] up there, too
[name_f][/name_f]of the ones ive met in real life, my least favorite spelling is [name_f]Katlyn[/name_f] because to me that should be said as kat-lynn (ive even known one who went by [name_f]Kat[/name_f], like the animal… but her full name [name_f]Katlyn[/name_f] was pronounced kate-lyn!)
[name_f][/name_f]im also not super keen on [name_f]Katelyn[/name_f]. it just strikes me more as a smush name [name_f]Kate[/name_f] + [name_f]Lynn[/name_f] than a name in its own right