I'll try to answer partially.
"It is forbidden to recruit spirits" - you cannot hire ghosts.
It is forbidden to enter the pyramid because it can drastically disrupt the game's balance. Building a level 5 magic structure requires a lot of resources, but breaking into the pyramid is not the most difficult task.
Players do not generate maps. They choose one from a standard set or agree to play on a non-standard map. Generating a random map in the second Heroes game leads to results that make you want to swear (by the way, my long-standing dream is a random map generator for the second Heroes game at the level of the generator in the third game. If someone does it, they will be a true SUPERHERO!). A ready-made save file is almost complete certainty, so a number of purely online features are lost, such as luck and excitement.
Regarding the turn of a redeemed hero. Initially, this was done to prevent abuse of the hit-and-run tactic. And checking for "not moving" is very difficult, only by looking at the save files...