Of light blue iris, I probably like the following the best:
Absolute Treasure -Tasco
Through the Clouds - Ghio
Abiqua Falls - Schreiner
None rebloom, but they all bloom over a nice long period in the spring. Absolute Treasure is a little taller than I like (42 inches), but it seems to stand up to wind a lot better than you'd expect for an iris that tall. Through the Clouds has a reputation for being a fussy grower, but it's always done great in my garden.
It is hard to find a true blue dark blue iris, most have at least some violet. Lake Taneycomo is probably the closest to true blue I've seen but, to my surprise, I found I didn't like the color very much.
These three, which all have at least a bit of violet in them, are my favorites:
Donaghcloney - Richardson
Adriatic Waves - Keppel
Rippling River - Schreiner
None of these are rebloomers either, but they all put on a nice show over a relatively long period in the spring
