Indeed, Slogan, Mictlan should not be underestimated on this map. Their three important provinces are all rather well guarded.
As for your points, I have not completely scripted all starting provinces. With a few exceptions, it is possible for the three non-fortress starting provinces to have extra sites and in some cases to have one of the lesser features overwritten. Thus the starting situation is not
exactly the same in each game, there is some latitude for surprise - and it is possible to get mage recruitment in provinces I have not explicitly planned for.
Abysia 195 is one of these, so you just got lucky with an additional feature
Pythium does not own 202, Atlantis does, and it has a lab.
Man's province 91 has a scripted lab! If none exists in your game, could you please give list the terrain features present so I can see if something has gone wrong? (it should start with lab, Forest of Avalon, Jungle Temple, and White Man Hill - if it does not, I wonder whether the lab has been overwritten by something else)
Machaka should start with labs in 124, 137, 152, and 166 - all the places they are scripted to recruit mages. Only 154 is not scripted to have a lab. (Oh, and please name provinces by numbers, as most of the names are not fixed but randomly chosen each game by the game)
Jotunheim 17 has neither temple nor lab. That is because I am evil. I have only handed bonus temples out to a few select religious nations and Jotunheim does not qualify. As the ice druid cannot be recruited without a temple, I didn't think they deserved a lab either. (I still wonder whether I went too far when setting up Jotunheim's province 16, "Triple Peaks". That is one nasty conflux of magical energies)
R'lyeh 64 with the bonus void summoning site could, indeed, use a default summoner for jokes and giggles. Perhaps a cursed recouperating astral idiot that any sensible player would exchange with a Star Spawn... Hmmm. The opportunities are endless. Good idea!