The bottom line in future Amiga development is this.
If any new hardware is not backward compatible or had any new revolutionary hardware in the same manner as when it was first introduced the future doesn't look too bright.
What compelling reason would anyone have to buy this new machine? To now have two distinct Amiga systems each with its own hardware and software probably doesn't look to good right to most Amiga users. Certainly it isn't what most would like.
It's hard to envision that any "Amiga" user would go for such a beast. To do so would mean users are ready to either sever the ties to the old system in favor of a new alien one or they're ready to continue to support two systems.
Amiga users who still actively use their Amigas are looking for a melding of old and new in one box so that then everyone can truly move off of the old hardware without having to worry about losing any investments in software made over the years. Demos, games, utilites should all work as they had in the previous systems, but on something far better and new. Regardless of how good a new Amiga may be, if it doesn't have backward compatability then why should anyone buy this system over a Mac, a PC? Both have a few operating system alternatives to choose from.
I would not even look at a future platform if it weren't backward compatible. And that will be the key to any successful future Amiga. It'll have to take over from where Commodore left off. AGA, then move forward from there. However difficult it may be to create such hardware it has to happen to bring all Amiga users onboard.