A lot of blue irises lean toward violet, which is a color I like. But I also appreciate those that are more nearly true blue. One of my favorites there is Queen's Circle:
One of my favorite horned irises is Blue Fin:
There are also some nice historic blue irises. Here's Tango:
And Tyrolean Blue:
All are tall bearded. Tango is a midseason bloomer, and the other three are mid to late season bloomers. Blue Fin is listed as a rebloomer, but I don't know how dependably or how far north it reblooms.