Interesting groupings and I agree that there is no generally accepted definition of 'bluewater'. Some specific comments on your Trans-oceanic and Voyaging designations:
T-O - crossing an ocean is not remotely like crossing the biggest lake there is in terms of days from shelter, rescue possibilities, weather (assuming in both cases you are doing it at a good time of year. There should be no mention of high latitudes here at all - that is a different kettle of fish entirely. Until the pirates in the Indian Ocean problem, the routine circum nav (if there was such a thing) was in tropical or subtropical waters. Now you have to go around South Africa and you pick the best season for it and really listen to the weather. If you are doing a coconut milk run you still have long times at sea (more than 3000 miles to Marquesas for example) and will be in lots of places with no repair facilities - eg Galapagos, Vanuatu, whole bunch of other places that are certainly not off the beaten track.
Voyaging - see above, you also need the versatile sail plan. For either you need really good ground tackle.
I think a better grouping of the last two would be something like 'Extended cruising' which is what we are doing. We are going off the beaten track at times - for example, we went to Easter Island from Galapagos instead of Marquesas but basically looking for a circumnav that is as non-dramatic and pleasant as possible. BTW, I think you need to add a very stout rig and reliable self-steering to both. We got knocked down (not talking Cape Horn - it was something like 400 miles from Tahiti) and just read a friend's blog. Their autopilot quit 6 days from Durban, South Africa and their spare they could not get to work either. Six days of handsteering with a 2-person crew is not something you want to do too often in life.
The second group I would call 'Expedition Cruising' for lack of a better term. These are the folks who go around Cape Horn or visit Baffin Island or the Aleutians (typically high latitudes). Their needs (rugged boat, self-sufficiency) are similar to the extended cruisers, just that much more so.
Also, your description of racing boats needs to be extended, but I will let racers do that.
Heading back to Lake Ontario for this summer. Relatively few stops along the way from Grenada. Martinique, Guadeloupe, St. Martin (must have something to do with the French food), then Bermuda, New England and up the Hudson/Erie Canal. We were going to go via Newfoundland and Labrador but June remembered that one of the kids is getting married this summer - details, details!