I don't mean to sound pushy, but I'd love for there to be some discussion regarding the viabiltiy of QEMU and perhaps any intentions of releasing a build - I think this would be suited more as a question rather than a presentation point however.
Optional reading spiel:
It's no secret - I'm a more than a bit passionate about having a working and stable QEMU build for ArcaOS (I've got a few posts discussing it). In addition to being a perfect fit for the 'retro gaming' front (namely anything from Windows 9x requiring DirectX) which Arca Noae wants to approach, QEMU would very much be a welcome replacement to the problematic, featureless, resource-intensive and ever-aging Virtualbox.
As long as ArcaOS can not solve the RAM Problem on modern hardware (younger than 2016) it will be a dead end for the retro ambitions as well as the virtualisation solutions, even for the new browser or the use of Open Office. With a maximum usable RAM of 1 to 2 GB it is simply unusable. As long as you stay with (selected) hardware up to 2015/2016 you can still have 3 to 3.5 GB of RAM, and therefore it may be possible to use QEMU etc.
Using ArcaOS on hardware younger than 2016 can make sense for industrial users, but as soon as you depend on more RAM than 1GB the only solution is to use it inside a Virtualisation like Virtualbox, VMWare etc. under Windows or Linux. And if you do that, you can have 3D accelerated Windows 98 with these Virtualisations side by side with the virtual ArcaOS.
Once you come to that point, that is, where I am now, and you want to use OS/2 inside a Virtualisation as a "real" Retro machine, than you can also use plain Warp 3 or Warp 4 as it makes no difference. Warp 4 is even better for Retro, because of the use of these new windows managers some programs are not that usable with ArcaOS than those are with Warp 4.
And if you want to have a certainly real "real" Retro feeling, I would like to advice to build your own Retro PC. I did this for Warp 3 with a 486AMD DX2/80 and for Warp 4 with an IBM 686MX PR300 CPU with "OS/2 Tailored" Hardware. Both of these Retro PC does have Pure DOS installed, available through the OS/2 Bootmanager.