Here was my remembrances when I asked Burtt on this issue:

http://originaltrilogy.com/forum/topic.cfm/Star-Wars-Tantives-Orange-Items-Thread-other-unintended-objects/post/592758/#TopicPost592758

I think listing out places where we believe a major/minor branch is made in the taxonomy and why is something to consider next. For example, were early VHSs made from a lower generation source and maybe the Definitive Collection or one of the releases at the end of the VHS era used a different source, something 'better' or closer to the film source. Did Widescreen and Pan/Scan work from the same or different sources?

The other problem considering a total film taxonomy is at any time they could replace a shot, because of SFX, crawl, credit, subtitles they all cause the taxonomy to bifurcate.

Would it make sense to split the definitions to reel numbers. Do some of the middle reels have less SFX and might not have been likely to have changes over the years?

Or conversely, find releases which share many traits and that helps whittle things down.

*EDIT*

What the Wookiegroomer split versions did for the research into SE identification (doubleofive's pages and Harmy's DeSps), SWTax needs a multi-release presentation to help the work along. It's a pain finding one thing to look into then opening up 7-15 releases for that specific frame. So what 5-10 releases would people consider good candidates for the next WG-like-splits?