You may be a better pilot than me, but I fly exactly the same i.e. 40-50 hours per year in a PA28 (renting from a RAFFCA club - a good deal if you can get it) and although I accept the legal arguments that the IMC minima (500/600ft) are only advisory, I wouldn't personally go lower than that by design.
In fact, I set my personal minima at 1000ft cloudbase/4500m visibility (if you break out of cloud at 1000ft the runway is around 4500m away on a 3 deg approach) unless I am in good recent practice in which case I might go to 800ft. And I am in the lucky position that I can get an ILS into my home base free of charge pretty much every time I fly, and I do. I do find my ability to hold the ILS deteriorates noticeably beyond 500ft - and there's a world of difference between practising that in VMC, and doing it for real being bumped around in IMC.
FWIW I have around 350 hours total now.
Tim