I believe there was an issue with the prereqs letting barbarians get free disciples in the last release which I think I fixed on my end a couple months back.
Some more recent changes I have made include:
Getting rid of the multiple summons from affinity spells.
Granting summons from affinity casters better bonus promotions. (Einherjar get Demon Slaying. Pit Beasts get Scavenger. Spectres get Fear. Treants get Forest Stealth and don't require a forest for an affinity caster to summon, and will get other perks based on terrain. Fire elementals get fire affinity, water elementals get water affinity, air elementals get air affinity, earth elementals get earth affinity, Wraths get death affinity. Ice elementals get slow if the caster does not have affinity).
Granting an affinity caster the xp from its dying summons that has the proper mana prerequisite. (Currently they get 100% of the xp, but I am thinking of scaling it down. Maybe 25% per channeling promotion would be better?)
Eliminating the caster's free xp based on Dimensional promotions from summons regardless of their prereqs.
Changing Extension 3 and 4 to be more like Extension 1 and 2, by making them grant Navigation 1 and 2 instead of Blitz and Herald's Blessing respectively.
Changing Extension to require Channeling 4 or Divine and not be limited to Coven units.
Reducing the base movement of the summons who formerly started with 2 movement points, as too many Extension promotions could make them too fast.
Changing most of the delayed casting spells to ordinary immediate casting spells. (I may change this back once lfgr fixes the bug with delayed spells miscasting)
The Without Arda promotion makes Divine casters more likely to miscast when outside of areas where their religion is dominant.
Allowing the Council of Esus priests to attack like other priests.
Ira Unleashed is back to being an Avatar of Wrath specific spell, as I never really thought it fit Carnivean.
Chaos 4 is now Mutation, which not only grants the Mutated promotion (and the various random promotions it can grant) but also randomly changes the base strength, defensive strength, movement, and damage of all living units (friend and foe) within a 2 tile radius. For each it picks a random number up to double the current value.
Creation 4's golden age does not miscast so often
Earth Affinity is no longer removed by gaining Flying, but Earth spells require ground contact and cannot be used while flying or on water tiles.
Stoneskin grants +3 defensive strength and 1st strike immune instead of +2 defensive strength and 3 first strike chances.
Earth Elementals are a bit stronger.
Death 3 Angels of Death no longer get the Arawn death promotions letting them cast destroy undead, but they start with Divine so they can cast Hallow Graves.
Enchantment 4 Automatons no longer start with Herald's blessing but have a new promotion that makes sure they are Permanent units with no duration limit or per caster limit. Their free affinity based on the tile now works properly.
Force 4 Purge Magic now has a range of 2
Shadow 4 "Summon Changeling" (which summoned multiple limited duration changeling units) was replaced with "Replace with Changeling" (which works like a less resistible version of Domination, which gives you permanent control over a rival unit and gives that unit the Changeling promotion.
Sun 3 Aureales no longer have divine, but those from affinity casters get affinity and can cast blinding light.
Undeath 1 Skeletons no longer start enraged. Undeath Affinity Skeletons no longer start immobilized. (They use the same dummy promotion as Automatons letting me turn a temporary summon into a permanent summon, but their PyPrerequisite still limits the number you may have at once.
Spectres no longer start with Fear, but it is given as a promotion perk for those summoned by casters with Undeath Affinity.
The Raise as Undead spell no longer requires any channeling promotions, but channeling promotions increase its range. (Now that I think of it I may change that to Extension promotions increasing its range.) The spell now requires Undeath Affinity and a Tower of Necromancy. Raise as Undead can be used to gain Barbatos, while Mas Resurrection can be used to get the other Imprimatur Council members.
Edit: To keep the two Death spheres more balanced, I just added a Free Sluaghs spell allowed by The Tower of Necromancy with the Arawn Death affinity. This transforms undead summons back into Sluaghs that could be resurrected later.
Sons of Discord no longer has the Discord civic and no longer locks you into war.
Sons of Discord units gain the Rebel promotion when not at war, but this can be removed via an Arena battle.
The Disrupt spell has been fixed to properly work with Agonists and no longer be tied to the Council of Esus/Undercouncil.
Summoned Imps gain Channeling II (but no affinities) and are no longer permanent summons
The Counselor unit is now a Brotherhood of Wardens religious champion, with spirit 1-3 instead of spirit affinity, not an Elohim berserker UU. The Merry Dancer cannot be trained, only created from demons by the high priest spell.
I am wondering if the Sons of Discord and Cult of the Dragon mechanics are too similar. I'm tempted to streamline things by eliminating the Dragon Fanatics and Wyvern Riders entirely. The art for just those units (including unique versions for each dragon) take up more space than 10 other new religions combined. I may need more time to think of how I'd most want to implement this cult and so might not change anything before the next release.
I have not had any crashes that asked to generate a dump file and complained a memory leaks since resetting my operating system. The game seems faster and more stable now in general, but I am still getting the occasional crash with no warning or explanation. I've found a fixed a few bugs but I don't think they are relevant to any crashes. I have found that when the AI seems stuck in a loop I most often can use worldbuilder to make their units skip turns rather than having the whole program freeze up.
The ruthless Ai is still really bothering me. I had hoped to include the next MNAI update from lfgr in my next release to stop that, but I think I think I will aim to have something ready to release on my birthday (one week from today) anyway.