Yeah, practically a good max threshold you'd want to allow would be either the classical n=3f+1, allowing each stakeholder to elect max f replicas (Where we got our max n given by 20). But that usually applies more in the case of the classical BFT protocols (PBFT and alike), doesn't it?. Doesn't Steem follow the classical 51% threshold we see in most PoS and PoW?

I disagreed with the point of:

even if not all of them

Since, with less votes they should be able to elect even less.

I do get the point with the coverage though, and I think it is a good idea to have no limit at all where votes could aggregate much more, which would make it practically impossible to elect any top witness for a single stakeholder. At the same time this could motivate big stake holders to vote a large quantity of capable witnesses (to increase this coverage) which would also lead to a denser field (making the witness election process more interesting - leading in practice also to the situation I was wanting to achieve).

But in this context I think either you got a small amount of votes to avoid the big influence of a single stakeholder, or you have a fairly large amount of votes to achieve this high level of coverage.

I would have to do the math behind it, but I feel 20 would be the worst possible threshold, and 30 also not being very great.