I remember PAL:Hi-Res Laced on my 25" TV and it wasn't too pleasant.
:-D
You could try getting a screen filter and that might reduce the
flickering (and strain on your eyes) but the best bet is to get a PC
monitor and a Scandoubler/FF like the EZ VGA Plus.
These will only flicker-fix in 31Khz PC modes so there's no point in
getting one for your present 15Khz Amiga monitor.
You could try a Microvitec monitor though, they might have the unusual
ability to be 15Khz and 31Khz compatible.
I know there's a nice 17" CRT called the Microvitec 1764 which is
Amiga design and a Microvitec 1701 with 9-pin VGA cable.
Both are good bets as well as NEC Multisyncs.
:-)