Quick update for this mod.
First off, on the above ideas:
1-3) On the backburner for the moment
4) Making Mobility, Enchantment, Combat and Terraforming available for research. Done, although I haven't checked to see what happens if you've already picked these spell lists in the Sov creation tree. I've accomplished this by creating a new list (KeySpellBooks), which points to 'spells' that give you the associated spell lists, plus a cantrip.
The cantrip is a low power spell that can augment your Sovereign in a small way (example: +1 to Attack for 5 turns, 1 Mana to cast). This gives Sovs a unique boost over normal units (these spells are Self only), and allow the Spell List Icon in your spellbook to continue to be useful i.e. not just occupying space).
5) Playing around with Spell Lists tied to Shards now. Haven't decided yet if you'll just gain the list automatically upon successful harvesting, or if this will unlock a 'spell list spell' for Arcane Research. Thinking...
6) Haven't decided yet what to do with what's left of the Magic tree (after spell lists are removed).
Sooo, going forward:
a) This mod is 'broken', in that you won't be able to build some structures currently (noticed this today, my bad). As I am planning to redo some of these anyways, that isn't necessarily a problem. You can still download it and see what I've done so far, but I would not recommend using it for playing purposes until I upload an updated .zip file. The baseline changes have been done on my end, I just need to playtest real quick to make sure everything is fixed. You may be better off waiting for my more extensive changes that are being worked on now.
b. Once the 'hotfix' release is posted, I'll upload the Spell List Migration part of this mod next. Should be in the next day or two.
c) This mod will include a 'fast start' option, which gives each capital +1 Materials/Tech/Arcane per turn, built into the Beacon Of Hope/Tower of Civilization structures. This should help a bit with any 'famine' situations that players may encounter, and will make capitals that much more important.
d) After I have migrated the Spell Lists, I'll be working on Materials/Weapons/Armors next. Essentially, this will tie the availability of various weapons and armor to specific structures. Equipment will be available anywhere in your kingdom as long as you've built at least one forge somewhere, unless I figure out how to 'check' to see if a specific city has the structure in question. Once this part of the mod is incorporated, I'll be renaming this mod, as it will have become more of a top down redesign at that point...