I would much rather do an hour long, multi-staged difficult quest to get a new kick-ass magic spell with a 2.0 multiplier than spending two hours on this forum trying to figure inner workings of a complex battle engine mechanic.
Ok, what is an interesting quest? It is a) exploring (but we don't have EE, and our city is not big enough); b) fighting (good BE required); c) dialogues, preferably nonlinear (we don't have a writer for such stuff); d) decent reward (the only thing we have covered, either slave, item or battle skill).
Skyrim come down to choosing any one single magical line and reducing spell cost to bare minimum, other mechanics like mana regeneration be damned. In the end, by level 30 - 40, you'll be sniping Frost Dragons with frost spells like they are mere flies.
Since you want to talk about Skyrim, I can tell you that magic is nothing there compared to archery, for example. Because you can improve bow damage to insane value with blacksmithing/enchantment/alchemy combo and then sniping any dragons on the max difficulty.
In decent game, you'd expect some mudcrabs and snakes with water alignment on swamp tiles, sand scorpions with fire alignment on desert tiles and so on. Not mentioning that desert time might weaken Water based mage due to a lack of liquid in the area.
Nah, Golden Sun (one of the best games about elemental magic imo) doesn't have such connection with terrain, except for a couple of scripted boss battles.
And yet you've created 250 items boasting almost 6k lines of xml code (40x40 map for our current setup is WAAAAY less than that)?
Yup, you don't have to clearly imagine all 250 items at the same time when you create 251 one. While you have to imagine the whole map.
What do you want to see in PyTFall? I mean, what would you be willing to create content for (like maps, enemies, rewards, items etc.). Or do you simply see value in adding complex mechanics to the battle engine scheme that we have now?
I wonder about maps. Maybe they should be random, with preset boss rooms, like in diablo games. This way you clearly won't know what to expect behind the corner, not matter how long you played. Btw, Alkion has a decent dungeon crawling EE, we could use it as a base.
Enemies, rewards, items I am willing to create as long as it is makes sense. For instance, currently it makes no sense to create a new weapon, since it won't be any different from those that we already have due to game limitations. But add, for example, elements to items, and you will have new fire/ice/etc weapons. Or add status effects, and you will have poisoning/dizzying/etc weapons.
Complex mechanics are needed for BE for sure. We can take a lot of interesting ideas from jrpg games. Currently we don't have any strategy during combat, you just click on enemies to attack them or use healing item when you obviously need healing. You could try Golden Sun (GBA and DS), some FF games (Playstation 1-2, not the recent ones, they are more like slashers rather than rpgs), Arc Rise Fantasia (Wii) and see for yourself. You don't even need consoles, emulators would be enough providing that you have a good pc.