i like using the knob mace a lot, but it being unbalanced really hurts its viability, imo. if it and the spike mace had the unbalanced tag removed, they'd be worth using "seriously" and actually comparable to one of the bardiches, bec, glaive, lhb etc. it'd also be nice to have a knockdown weapon that's not unbalanced or a short mace/baseball bat.
someone will probably point out that it would end up close to the old bec, so it could be slowed down a little (knob mace has 93 speed, spike has 91, maybe down to 91/89 respectively) and i think it would be in a good spot (though i think it would probably be fine with the speed kept as is). the knockdown doesn't proc all that often, and in terms of dueling it's one of the easiest weapons to track, so i don't think it would cause any problems.
free knob/spike mace from unbalanced hell