There are few limits to how exotic a cabinet design can get. But keep in mind that the cabinet is usually the most expensive part of the speaker. So re-working the HT3 in some of the ways suggested will only serve to make it a much more expensive speaker. It will likely not increase the sound quality to any appreciable degree.
The SoundScape 10's were designed to take the HT3 concept to the next level. And they certainly do that in almost every aspect. So, in a very real sense, we have already re-designed the HT3 (and named it the SoundScape).
My current inclinations are to leave the HT3 as it is. It is a very good speaker in its current form. If I think about re-working it, I immediately think about the driver selection, etc. In other words, everything would be on the table, not just the cabinet. In that case, it wouldn't end up being an HT3. It would probably be a totally new design and would probably be priced at about where the SoundScape is now.
That said, if someone wants an HT3 in a cabinet that looks different, we would certainly work to accomplish whatever that customer wants, including cabinet designs much like those posted above. That is a big part of what we do and I have no problem with that. It would just be more expensive.