Actually both those items are relatively easy. Cure potency will lead to bigger cures which are easily seen and can be calculated and the pumps fast cast will show up with recast of spells.

Now hard/time consuming ones would be like Augury Cuisses, Buramgh, Shigure Tekko, Tancho, Warder's Charm, Zoar Subligar

And impossible to gauge testing would be Metamorph Ring.

But yeah I'm all for expanding checkparam to show things like double/triple/quad attack, macc, subtle blow, store tp, mab, etc. Both for this and just in general