Mary, you have enough Icelandics that you can cull a lot and still have all the genes that you need. Concerning inbreeding, domestic chickens have 39 pairs of chromosomes, we have only 23, domestic chickens reproduce at an amazing rate, if you take what you have and divide them into three groups, isolate these breeding groups for three generations, then do a variety of back breeding such as great grand nephew roo back to great grand Aunt hen, ans some third cousin back to first cousins you will be able to easily maintain genetic diversity, All those chromosomes are being reshuffled at every breeding, repaired and spit back out as a new creation.
In countries that had little opportunity to import for generations, such as Australia, a few Sussex came over with the prison ships and for a couple of hundred years the Australians have actually improved the breed with intense management. Our challenge is simple compared to theirs, all we want is genetically healthy and diverse Icelandics. I am excited because all I know about genetics and chickens doesn't exactly apply to my Icelandics, their genes are a new mystery to unfold!
I think in reference to the solid vs stippling vs spangling etc. All these patterns are visible in the dozens of pisc of Icelandic fowl in Iceland on Flickr.com
Truth be told we are exceedingly blessed with a breed thats greatest asset is its diversity, its genetic distinctness due to isolation over 1000 years, and the access we have due to modern transportation etc.
I love these because they are lots of fun and very little worry! Enjoy enjoy enjoy and if you are busy, sad, preoccupied, depressed, angry, .... well..... all the more ENJOY these little gifts, feathered jewels from the hand of God!
Andy