[Edit: to be clear, I am aware of the existing stuff...what I would like to see is the Amiga used to reimagine what a computer is - new hardware, new OS, new "web browser" (that ditches current conventions) ... I am aware this is a pipe dream :) ]
- No x86. The x86 platform is like a boring, ugly dude who has taken steroids and growth hormone for 20 years. He's bigger and stronger than everyone else, but he's still boring and ugly. The new Amiga should be as fun to code in asm as the 68000 was.
- Multimedia as first class citizen. None of this '70s character-mode fetishism you get in the Unix world :) On the Amiga, everything knew you had a graphics chip, hardware sprites and stereo sound.
- Good hardware integration. Imagine that your GPU was as accessible as your CPU, that you didn't need to install a ton of crap from Nvidia just to program it. I used to experiment with the Amiga gfx hardware in assembly language, from Basic, in a couple of pages of code. I miss how accessible the full power of my computer was.
I'd have to spend some more time thinking about the OS. On one hand, it would need modernization with regard to security, networking, Unicode, USB etc. On the other hand it was a lot more ergonomic than Linux, with hardly any historical cruft, and I'd never want to lose that.
The closest thing I've found to the "Amiga feeling" was when I was experimenting with a Playstation 2 emulator, and spent some time reading the hardware docs. It had a similar setup of exotic graphics chips hanging off a fat DMA system. However, the Amiga was far more than a straight games console, and its custom hardware was more abstract and flexible than you'd find in most consoles. (Compare the Amiga to the supremely powerful, but rigid Sharp X68000 for example)
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There is a new Amiga being developed. It is an accelerator board with a brand new 68080 processor. The thing is, it being FPGA, it actually doesn't need to be hosted in an actual Amiga any more. Therefore they are planning to make a standalone, essentially new Amiga. The Apollo 68080 Accelerator - New Amiga: http://www.apollo-core.com/index.htm?page=products
Also. This is what Amigas can do in 2019:
https://www.youtube.com/watch?v=Jh2nqjQzLWo
A new "Amiga" would be something completely different than the old Amiga (which has long been surpassed by PCs with high-end graphics cards) or the current software/hardware model of a PC (which could be improved in many ways if you decided not to be a slave to current hardware and software standards).
I'm not sure what that means, really, because creating something new and useful is a hard (but not impossible) task. It really does take commitment in these days of software that is POSIX everywhere and (graphics) hardware that is sometimes interesting and high performance, but very buggy and effectively, probably intentionally, undocumented.
It's a standalone board that runs Amiga Firmware and boots the Amiga OS. As such it is a new Amiga.
Honestly, though, now would probably be about the time for Amiga to make a bit of a comeback; with the advent of really awesome web applications, the actual operating system is becoming increasingly irrelevant to most users. If we could get the two big browsers out there (Firefox and Chrome) to make decent ports to AmigaOS/AROS, then I could conceivably some of my non-tech friends using it without even fully realizing it.
Sadly, though, I think that's too little too late; non-technical people seem happy enough with their Chromebooks, and technical people will be hampered by the lack of software available for Amiga on current computers.
There were some limitations with systems of that era that a design reboot should overcome: security, access to tcpip.