I have a few more blues to add to this list I think my favorite is Adriatic Waves that Kent showed earlier it really is a beautiful color of Blue and I like the ruffles :)
I think next for me last year was Ride The Waves it was awesome and really stood out amongst the other plants Here is a close up and then a garden picture of it so you can see how it stands out, if I had too pick one blue to splurge on this would be the one. It had a long bloom time, don't remember how many buds were on it but I had lots to work with, used it quite a bit last year it sets pods and had very fertile pollen.Everyone that saw it last year stopped and commented on it Highly recommended.
Sea Power is another really good Blue and will probably be one of the last to bloom in the garden or at least it is here spectacular grower and parent it is another one to consider.
Here are a some more to consider that I thought had good color
First Wave and Lynette Blue
Mythology & Aqua Fresca
One more I really like called Honourable Lord it's more of a Bi Color but the light Blue Standards and the dark falls really make it stand out in the garden.