I think both [name_f]Ophelia[/name_f] and [name_f]Odette[/name_f] go well with [name_f]Primrose[/name_f] [name_f]Grace[/name_f] (which is beautiful btw)! I slightly prefer [name_f]Odette[/name_f] with [name_f]Primrose[/name_f] I think. 
[name_f]Aurora[/name_f] is also lovely with [name_f]Primrose[/name_f]! 
Some ideas:
[name_f]Marigold[/name_f]
[name_f]Lillian[/name_f]
[name_f]Margot[/name_f]
[name_f]Lilibet[/name_f]
[name_f]Elspeth[/name_f]
[name_f]Lucinda[/name_f]
[name_f]Arabella[/name_f]
[name_f]Aurelia[/name_f]
[name_f]Annabel[/name_f]
[name_f]Paloma[/name_f]