Nice 7 years old threat.
Beside PatchControl is SaferPatches. Debug tools are always nice to have but not all are hacks IMHO.
Stuff I use under OS3.1 A1200 040 AGA:
MMULib Tools (only few hacks)
envhandler (wouldn`t call it a hack)
LoadMonDrvs (wouldn`t call it a hack)
FPPrefs (FullPalette) maybe no hack
DRemind is no hack
HRTmon (do you would call it a hack?)
Yes, my system runs stable and fast because of some hacks. It takes some time to behave it so but it is worth.