Mine were all blue, from a breeder with a very large flock and hers were ALL blue. A nice blue too.
I had one prairie bluebell and her eggs were blue but very pale. Powder blue. Something in their genetics I think.
The brightest blues I've had were from Easter eggers. Tending towards mid...
I had Whiting True Blues - definitely recommend. Great for all your criteria, except maybe eggs are not reliably Large? I didn't weigh and don't have WTB right now, so don't have numbers to say for sure, but they definitely weren't huge (though I did have a lot of extra larger layers at the time...