It's almost like playing an entirely new game again:
The map has been changed to an infinitely explorable, seamless transition and has been massively expanded.
A single map can now contain multiple cities/fortresses.
Combat now takes place entirely in real-time directly on the map.
Card skills can now be triggered with a single click. You can also use items to heal during combat.
All map elements can now be destroyed, including rocks, treasure chests, etc.
The old dialogue system has been temporarily disabled and replaced with simple touch-to-interact conversations.
Party formation, video, and some other systems have been temporarily disabled.
Over 100 new building types have been added. Each race now starts with different buildings.
The save/archive system has been completely rewritten.
.... Since the changes are too extensive to list every single one, I'll leave it at that. In any case, it basically feels like a brand new game. Performance is running pretty smooth right now.