So my weirdo husband (yes weirdo, it is so difficult to pin down what he likes, he swings from super traditional to Irish/Welsh hard to pronounce names!).
He likes [name]Sarah[/name], and I said I wanted something less common.
So his choices were [name]Saoirse[/name] and Eirys. While cool, and strong, I don’t feel as if they are “it”…any suggestions which might fall into his obvious love of “r” and “s” would be helpful!
It seems he likes R, S, and Irish/Welsh names! What about [name]Carys[/name]? It seems to fit his style perfectly!
Other suggestions…
[name]Aislinn[/name]
[name]Shannon[/name]
[name]Sinead[/name]
[name]Siobhan[/name]
[name]Sorcha[/name]
[name]Roisin[/name]
[name]Rhiannon[/name]
Other names with the R/S sound
[name]Sarai[/name]
[name]Seraphina[/name]
[name]Sophronia[/name]
[name]Rosalind[/name]
I love [name]Eilish[/name] and [name]Ailish[/name]!
Well, my name is [name]Sarah[/name], haha, so I love that one! 
(It IS very common though)
I really love your husband’s pick Eirys!!! I also love the previous poster’s suggestion of [name]Carys[/name] (which is similar).
Irish/Welsh names with both S and R my favorites
[name]Roisin[/name] (anglicized as [name]Rosaleen[/name])
Brisen
Rhosan
[name]Seren[/name]*
Seirian
Irish/Welsh with either R or S
[name]Rhiannon[/name] (nn [name]Rhia[/name]!!)*
[name]Ceara[/name] (anglicized as [name]Keira[/name])
[name]Muireann[/name]/Muirin*
[name]Caron[/name]
[name]Eleri[/name]*
[name]Ailis[/name]
[name]Maire[/name] (anglicized as [name]Maura[/name] or [name]Moira[/name])
[name]Shannon[/name]
[name]Catrin[/name]
[name]Aislinn[/name]*
[name]Brenna[/name]
[name]How[/name] about [name]Seren[/name]?
[name]Seren[/name] is nice, but our last name ends in an “n”
Also [name]Carys[/name] is lovely, but our LN begins with a “Car” - last names can be so tricky!
[name]How[/name] about:
Cersei
[name]Ronan[/name]
[name]Wren[/name]
Reesa
Hmm…I love previously mentioned [name]Carys[/name] and [name]Seren[/name], so I’m sorry they don’t work! Maybe you’d like [name]Aoife[/name], [name]Niamh[/name], [name]Sorcha[/name], [name]Una[/name], [name]Ciara[/name], [name]Iona[/name]?
I adore [name]Saoirse[/name]. So beautiful. Eirys is pretty too.
[name]Caoimhe[/name] (Key-vuh) and [name]Eilish[/name] (Eye-lish) are a few others I like.
Gwenwyn
[name]Bronwyn[/name]
Awen
[name]Tegan[/name]
[name]Ceri[/name]
[name]Wynn[/name]
[name]Pembroke[/name]
Raewyn
Saorla
[name]Arwen[/name]
[name]Rhonwen[/name]
Eres
[name]Fiona[/name]
Rhosyn
[name]Nessa[/name]
[name]Arianwen[/name]
Saffir
A note–Welsh names (and maybe Cornish, etc.) that end in -wyn are boys’ names, while thos than end in -wen are girls’ names. Ex: [name]Bronwyn[/name] is a boys’ name, and [name]Bronwen[/name] is a girls’ name. [name]Just[/name] a weird little pet peeve of mine.
I love [name]Saoirse[/name] but what about [name]Eilidh[/name] (A-lee) which is Gaelic?
Those are Irish right? Others are [name]Roisin[/name], [name]Sinead[/name], [name]Niamh[/name], and [name]Aoife[/name].