I like west to east as well since it gets the most boring part of the trip out of the way early, that being from Clinton to Sedalia. And logistically it's easier for me since I live 4 hours from the most eastern end and I can get the train ride over with at the beginning. Shipwreck's comments, as usual, are spot on.

Wasn't it about 7 or 8 years ago that someone attempted to put together a small group ride on the Katy from this forum? I don't remember the details and I may be wrong but I don't think it came off yet they talked about trying it again, so who knows, if you're not too soured on your experience, maybe a bikeforums group tour on the Katy is in your future.