1) It doesn't say that it only applies to battles, and there's also a footnote in the manual.
2) The two missing spells in "Lord of the Land" is a valuable observation.
3) I haven't dealt with creature abilities. To be honest, I don't feel like dealing with it right now, and I don't know when I will.
The original text says 40%, but I haven't checked.
For the third time today, I updated the mod on the previous page, adding a fix to "Lord of the Land".
1) "The hero receives +1 to one of their primary attributes for each [] level, including those already gained, and an X% bonus to experience gained in battle" - description from the vanilla game.
2) The mention of "Earthquake" there is meaningless. I removed it in my version.
Actually, I initially thought that "Lord of the Land" really gave this bonus, but it goes nowhere due to the lack of scaling from magic power. Nothing like that - even if we enable scaling (and destroy a Castle with a single cast with normal magic power), "Lord of the Land" won't do anything for "Earthquake". Not in HotA, not in SoD, nowhere. Before HotA, it only worked on "Fire Trap".
3) Well, I did say that I fixed "Storm Caller" in my version. I asked if anyone needed it or not.
I'm aware. I asked because in the original/SoD, the descriptions of Wind/Veil corresponded to the effects. In HotA, the abilities were enhanced, but the descriptions remained the same. With "Devil's Strike," it's unclear whether there's an error in the description everywhere, or whether the percentage was reduced in HotA (40>30), but the number in the text wasn't changed. I'll probably test it myself.