I think before any movement away from clan tartans takes place a general change in mindset must take place.

When most people (those outside this and similar forums) begin to look at the kilt and a tartan they have some general beliefs (right or wrong). They see the kilt as a Scottish garment and believe that to wear the kilt it must be made in one of the traditional clan tartans. They also believe that to wear a particular tartan, they must have a link to the clan it represents (no matter how nebulous). Thus they will try to find the clan tartan for which they can find the closest link.

Now, I have a MacIan tartan because it was my closest link (my grandmother was a McKean). I still wear it occasionally, but I'm finding that I wear other kilts because of closer links - my US Army tartan and my personal Dove tartan. I also have to say that I find myself wearing the dove tartan more than others, because it means more to me.