[name]Natasha[/name] elizabeth
natasha marie
natasha lynn
or
[name]Lindsee[/name] clair
[name]Lindsee[/name] [name]Beth[/name]
I like [name]Natasha[/name] more than I do [name]Lindsee[/name] ([name]Lindsay[/name] is pretty dated–1980s–and the [name]Lindsee[/name] spelling looks trendy to me). You may also like [name]Natalia[/name].
I love [name]Elizabeth[/name], but I think that [name]Natasha[/name] [name]Claire[/name] has a better flow.
Some more middles with [name]Natasha[/name]:
[name]Natasha[/name] [name]Blythe[/name]
[name]Natasha[/name] [name]Belle[/name]
[name]Natasha[/name] [name]Pearl[/name]
[name]Natasha[/name] [name]Violet[/name]
Good luck! 
I do enjoy your thought of [name]Natasha[/name] [name]Belle[/name] and [name]Natasha[/name] [name]Pearl[/name]. The reason we are trying to fit [name]Lynn[/name] in therre is due to my great grandmother, [name]Lynn[/name] maybell (mable).
I definitely prefer [name]Natasha[/name] over [name]Lindsee[/name]. Would you ever consider using [name]Mabel[/name] to honor your great-grandmother? Or if you want something a little more exotic, [name]Maribel[/name]?
What about [name]Natasha[/name] [name]May[/name], or even using [name]Natasha[/name] [name]Maybell[/name]? I think it’s really pretty!
You may also like [name]Evelyn[/name], [name]Rosalyn[/name], [name]Linnea[/name], or [name]Linden[/name] as first names to honor a [name]Lynn[/name] (I love the sound of [name]Evelyn[/name] [name]Maybell[/name] or [name]Rosalyn[/name] [name]Maybell[/name]), or even a [name]Belle[/name] name like [name]Annabelle[/name] [name]May[/name] or [name]Mirabelle[/name].
[name]Edit[/name]: I also love [name]Olive[/name]'s idea of using [name]Mabel[/name].
Good luck!