Thanks for all the feedback. I've been traveling, so I'm online intermittently and couldn't respond earlier.
Thanks for reminding me about another consideration--buying one of EG's signature shoes. Both the Dover and the Ashby have the skin-stitched split toe and so they should display EG's signature style. I wasn't familiar with the Ecton, so I appreciate seeing the picture. I already own a brown and a black monkstrap, but I don't own anything with a split toe, so the Dover or Ecton would add more diversity to my shoe collection than another monkstrap would. I'm only in San Diego temporarily and I'll be moving back to the Midwest at the end of the year, so I would get significant use from a pair of boots.
As for color, I agree that dark oak is too dark and I don't think it shows the famous EG antiquing to full effect. I've never seen antique burgundy, but from the comments I read here, it is apparently also too dark to display the antiquing fully. I'm not sure how I feel about the lighter shades of brown like Edwardian or especially acorn. I don't own any tan shoes, so something in a lighter shade would add something new to my collection. How does the Edwardian or acorn compliment jeans?
The selection of a particular last seems to depend on how well a particular last fits the foot, as well as the styling. I have Timeless_Riders pictures of the various EG lasts saved on my hard drive and I like the look of the 606 and I also like the 888, which I have seen in person. It seems from the pictures, though, that the 606 is narrower than most of the others, including the 888. I tried on a Mackay (888 last) and it was a little snug near the seam for the toe cap, so I'm not sure the 888 or the 606 would be a good fit (although I really like the look of both). I've also tried on a monkstrap on the 89 last and it was a little large. Hilary will send several shoes for me to try on, but I would appreciate any wisdom that forum members might have about the fit of the various EG lasts.
Finally, it seems I would have a shoe of maximum versatility if it had a Dainite sole, or one of the equivalents, so I could wear the shoe on ice in winter. Is there any particular advantage to Dainite vs. Ridgway vs. Medway(is this what the 3rd option is called? I don't have my EG catalog with me) soles?
Thanks again for all the help and advice.