> There's no real way to translate the classic theme "as designed" to hi-DPI systems, AFAIK
The classic theme supports arbitrary sizes (in px or "device-independent" units) for both text and widgets, which addresses HiDPI and touch readiness. What it might have trouble with however is mixed DPI, where moving a window across two screens requires rendering it with different pixel densities. But that was not on the horizon in the Windows 8.x days.