Problem with "preferably in different areas and conditions" is the person may not be able to do this for financial or other reasons.
I understand that problem very well, but I don't think that standards should be relaxed because of that. Or actually, I think there should in fact be standards that required divers to experience different conditions to progress and to become instructors. The cards they will have are universal.
Stoney cove is a popular inland dive site in England and there are PADI instructors who have never left the pond! On the other hand, BSAC forces divers to experience different types of diving even to progress to the second level.
On top of a minimum number of dives (which can well be 100), I'd also require a combination of depths and types of diving.