I like all your boy names & middle names! So that doesn't make it easy...
I do however think that Joshua sounds better followed with Matthew, as Joshua Ash is a bit of a mouthful when you say it together- the sh followed by another sh.
I also think that Hamish needs to be with Matthew - as Hamish Ash is too much sh..sh sounding.
Oliver Ash sounds cool - and actually, Issac flows better with Matthew too - the 'ac' sound followed by 'Ash' is kinda similar.
Having said all that, the middle name is only something that will appear on legal documents etc, and you are unlikely to hear them said aloud together very often - so if you like something - who really cares??? I'm just being really picky to help you out!!!

Now for girls..... my 3 faves are Soraya, Jazlyn & Lylah.
I personally don't like Addison (reminds me of Maths ), Isobel is nice but SO common right now, and Lexi is cutesy but more of a nickname IMO. Plus I agree it doesn't go with Elsie very well.
Soraya is likely the most unique and I think very feminine and soft sounding - prob my 1st choice there. What about Siraya? I like that spelling even better.....

Goodluck deciding!

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