What would be really interesting: porting DOSEMU 1.4.0 to it. This would give us a maintained unix-like OS combined with a huge abandonware dos library turning those old machines into something fun and maybe useful.
This. I literally rebuild DOSEMU yesterday after years of not using it. It used that mode extensively.
A good thing about DOSEMU against DOSBOX is that the first could run high end DOS game at amazing speeds as the environment was more like Wine than emulating the whole machine, so you could run Tomb Raider, Need For Speed, Duke Nukem 3D... on a Pentium II while 'simulating' a Pentium MMX or a Pentium 90-like speeds, if not more, being far closer to the performance you got under W95/W98.
And, as you said, booting SvarDOS either from a floppy or from an IDE->CF card it's straightforward.
Computers which use 16-bit Intel processors (80286 or earlier) are quite rare nowadays - most of them are 30-40 years old, and are more valuable to collectors than newer and more capable hardware would be. If you want something "useful", this isn't where you'd find it.
You can just run MS-DOS or FreeDOS directly on those machines, that's what the machines were made for.