I think [name]Ruby[/name] [name]Joy[/name] is adorable and perfect with [name]Sunday[/name]. I also like [name]Lemon[/name]'s suggestion of [name]Jubilee[/name]. The French spelling of [name]Joy[/name] is [name]Joie[/name], perhaps you would like that? But there is the risk of pronunciation issue some might think it’s [name]Joey[/name].
[name]Ruby[/name] [name]Joy[/name] is very cute and for what it is worth, I don”t think [name]Ruby[/name] is too stereotypical of a red-head.
If you aren”t too worried about unique names, maybe Joyful would be an option for you? Joyful [name]Anna[/name] would give you a [name]Joy[/name]-[name]Anna[/name] nn that matches [name]Sunny[/name]-[name]Lou[/name] (so cute by the way).
Or how about [name]Joya[/name] [name]Belle[/name] - [name]Joy[/name]-[name]Belle[/name] I guess you could venture into creating the name Joyabelle or even Joyanna
I love [name]Joy[/name] with [name]Sunday[/name]!
If you’re still looking for suggestions, though, how about [name]Felicity[/name]?
My second daughter is [name]Sunday[/name] [name]Florence[/name] and her big sister is [name]Stella[/name] [name]Lily[/name]. 
Interesting that we chose [name]Sunday[/name] because that was the name of an important art patron in Australia in the 30s-40s- and one of her best female artist friends was [name]Joy[/name]. [name]Sunday[/name] & [name]Joy[/name] sound great together!
We are expecting our 3rd child and I am struggling with a 3rd girls name (we don’t know what we are having) must say I do feel a bit stuck with S names! 
I would just go for [name]Joy[/name] if you both love it. I think it sounds lovely with [name]Sunday[/name].
But if you really want a longer name, [name]Johanna[/name]/[name]Johannah[/name] might work. My mom’s friend’s daughter is [name]Johannah[/name] [name]May[/name] and she goes by [name]Joy[/name].
Adio Girl African [name]Born[/name] on [name]Monday[/name]
Adwoa Girl African [name]Born[/name] on [name]Monday[/name]
Adzo Girl African On monday born
Coujoe Boy African [name]Monday[/name] [name]Born[/name]
[name]Jojo[/name] [name]Both[/name] African [name]Monday[/name] born
Kodwo Boy African [name]Monday[/name] [name]Born[/name]
[name]Kojo[/name] Boy African [name]Monday[/name] [name]Born[/name]
[name]Tanesha[/name] Girl African [name]Born[/name] on [name]Monday[/name]
Taneshea Girl African [name]Born[/name] on [name]Monday[/name]
[name]Tanisha[/name] Girl African [name]Born[/name] on [name]Monday[/name]
[name]Tenisha[/name] Girl African [name]Born[/name] on [name]Monday[/name]
Tinisha Girl African [name]Born[/name] on [name]Monday[/name]
I would call her [name]Joslyn[/name] or [name]Jolene[/name] with the nickname [name]JoJo[/name]. [name]Poppy[/name] is nice for a red head as is [name]Ruby[/name], [name]Roux[/name], [name]Sorrell[/name] and [name]Scarlett[/name]
I think I love [name]Ruby[/name] [name]Joy[/name]!
I think [name]Ruby[/name] [name]Joy[/name] is adorable! I don’t know what’s wrong about that. And if you feel like it’s still too short, just add in another name. [name]Ruby[/name] [name]Isla[/name] [name]Joy[/name]? I don’t know, something like that. I think it’s very cute indeed. 
And honestly, [name]Joy[/name] is fine as a first name, too. It’s a very eloquent, beautiful and elegant name. Congratulations!
I love [name]Sunday[/name] and [name]Olivia[/name] together and [name]Sunday[/name] and [name]Grace[/name]. [name]Olivia[/name] [name]Joy[/name]? [name]Grace[/name] [name]Olivia[/name] [name]Joy[/name]?
What about [name]Juniper[/name]? I like its spunkiness. [name]Ruby[/name] [name]Joy[/name] is nice too and it does sound good with [name]Sunday[/name] [name]Louise[/name].
I was actually going to reccomend [name]Jubilee[/name]! It sounds perfect with the name [name]Sunday[/name]. It is actually my current choice for our future 2nd daughter…lol. It’s meaning is actually quite joyful, so it would actually be a great way to get to that meaning.
Here are some suggestions below:
[name]Jubilee[/name] nn [name]Joy[/name], [name]Jewel[/name], [name]Jules[/name], [name]Billie[/name], or [name]BeeBee[/name](or even JuJu [name]Bee[/name] lol)
Lovejoy nn [name]Joy[/name] or [name]Love[/name] or [name]Lovey[/name]
Loveday nn [name]Love[/name], [name]Lovey[/name], or [name]Day[/name]
[name]Valentine[/name] nn [name]Love[/name], or [name]Val[/name], or [name]Valen[/name], or [name]Tiny[/name]
[name]Cleopatra[/name] nn [name]Cleo[/name]
[name]Penelope[/name] nn [name]Penny[/name] or [name]Pepper[/name]
[name]Clover[/name] nn [name]Clo[/name], [name]Chloe[/name], or [name]Love[/name]
I also forgot to add [name]Juniper[/name] nn [name]June[/name] or [name]Junie[/name].