As I understand it you are not interested in buying a Vampire anyway.
Just as soon as they make a CD32 version

There will be no new 3.1, and expecially no 4.X for 68k how some (you?) seem to fantasize. Hyperion wants to sell 4.X on real PPC hardware, even the many emulation customers are officially not supported. All that "they will backport 4.X to 68k" are wet dreams distant from any reality. What you might have got (at best) a slightly improved 3.1.
Hyperion wants to sell products that make money - PPC is simply where they've ended up (unfortunately) - and the copyright scenario has changed drastically since the days of the Pegasos. Now the classic hardware market's getting a shake-up that couldn't have happened until products like the Vampire appeared so opportunities are presenting themselves that weren't viable before due to licensing and commercial viability.
That doesn't mean you're wrong - just that if the rights-holders wanted to exploit OS 3.x to make some money, the chances of creating a product that sells are potentially greater now than they've been in a long time (since the Vampire is the first classic Amiga product to come along that's *vastly* more capable than anything we had before).
Clearly there's some will from Cloanto since they've been making minor updates to 3.x for distribution on disk, ROMs and as part as Amiga Forever. I've already stated I highly doubt any of this will result in an updated 68k OS but perhaps if there's a demand for it (due to a product like the Vampire) then it will (and clearly devs like Thomas are open to the idea and as a user I'd be interested in buying it).
Aros is a reimplementation of the 3.1 API including intuition, gadtools and many others.
Upon it you can use not only the limited default desktop but also Scalos and even Magellan (both old one and new one). When using Magellan you can even use MUI 3.8 on it (what I did). It includes additional several patches by default, moving screen out of window, AHI, CybergraphX and so on, there is PCI support and USB-Stack (Poseidon), both on 68k untested but potentially working, network stack and so on. Wawa managed to get MESA/Gallium working on 68k (though slow but who knows what future brings).
Regarding AROS, I tried the Amiga Forever downloadable and it's impressive - really, really great work. But it's not the AmigaOS I grew up with and began a career as a digital artist using - and it never can be. If there's people out there using it and getting enjoyment out of it then that's wonderful and a testament to your hard work - but it's not something I'd personally choose to use - but that's just me.