[Fyron]

Proportions is definitely not a "must have" in that sense, as it vastly alters the gameplay in almost every way imaginable. It is not just a few balance tweaks or "fixes..." Great mod of course, just not the kind of thing that could ever be considered as an "official upgrade" by the developer.

Also, I believe that most (if not all) of the ideas in PvK's balance mod were used by PvK in Proportions... Directly combining them might be redundant, and could possibly violate some of the principles of Proportions (reproduction characteristic costs compared to rates of reproduction on Proportions, for example). It is designed more for a more balanced setup of racial trait costs in the stock game than such a radically gameplay-altering mod as Proportions.

Malfador has never put out any sort of "official blessing" on any mod. None can be considered an "offical upgrade," and there are a lot more great mods out there than just these two.