Granted, I also love surnames on girls, but [name]Finley[/name] and [name]Quinn[/name] (Esp the longer versions you listed) is too matchy [name]IMO[/name]. I do like [name]Aquinnah[/name] [name]Jane[/name], but if there’s are chance they’d be [name]Quinn[/name] and [name]Fin[/name] a lot, then no.
I’d also avoid names ending in -ley for the same reason- like [name]Finley[/name] and [name]Hadley[/name].
There are gorgeous surnames out there- great sister names to [name]Finley[/name]. [name]Jane[/name] is a fitting mn in your case, and good with [name]Grace[/name].
[name]Finley[/name] [name]Grace[/name] and
[name]Cooper[/name] [name]Jane[/name], [name]Spencer[/name] [name]Jane[/name], [name]Parker[/name] [name]Jane[/name], [name]Callaway[/name] [name]Jane[/name], [name]Kendall[/name] [name]Jane[/name], [name]Destry[/name] [name]Jane[/name], [name]Averill[/name] [name]Jane[/name], [name]Tierney[/name] [name]Jane[/name], [name]Glover[/name] [name]Jane[/name], [name]Hemingway[/name] [name]Jane[/name], [name]Harper[/name] [name]Jane[/name] (popular)
You could also go with a surname-ish feel, sort of a tailored girl name like-
[name]Piper[/name] [name]Jane[/name], [name]Tanith[/name] [name]Jane[/name], [name]Margo[/name] [name]Jane[/name], [name]Bronwyn[/name] [name]Jane[/name], [name]Kimber[/name] [name]Jane[/name]
A place name or word name is tailored enough for [name]Finley[/name] [name]Grace[/name] too:
[name]Dallas[/name] [name]Jane[/name], [name]Savannah[/name] [name]Jane[/name], [name]Brooklyn[/name] [name]Jane[/name], [name]River[/name] [name]Jane[/name], [name]Cadence[/name] [name]Jane[/name], [name]Meadow[/name] [name]Jane[/name]