Well done for organising this. I'm descended from the Aytons of the Itteringham area in North Norfolk, but have had a number of contacts with people from the Gissing / Pulham Market line including George Ayton of South Shields who has a lot of well organised information on this line. If you're not already in touch with him, I'd suggest you e-mail him at firstname.lastname@example.org
and compare notes.
I have recently been consolidating a lot of material on the Itteringham line and trying to pull togeter the fruits of several people's research in this area. In the 30 odd parishes reviewed in the area around Itteringham (mostly for the mid C18) we have a number of variants of the name including Heyton, Heighteen (our own ancestor), Aytton, Haighten, Neighten, Aiton and Aitton, and have also observed a number of probably unrelated but partially similar names including Athill, Athow, Attue and Beyton.
My current thesis is of a possible origin for the name in the parish of Heydon, and there was a notable family of this name which flourished at Baconsthorpe and is recorded in 'Norfolk Families'. There a very few Aiton / Ayton / Heyton variant references in early Norwich wills (I have a complete index 1370-1857), but I must confess I neglected to review the 'Eighteen'; variant. I can easily do this if no-one else has covered the ground already, and make the (pretty small) consolidated index available on the web.
I've also considered setting up a limited one-name website for specifically Norfolk Aytons, but am waiting until I've consulted fully with others who have already done more work than me in this area. I'd be happy to coordinate if you're interested.
All the best,