I think this is an extremely important question.
People are making elaborate suggestions. Great. But we don't know if it is really possible to implement them.
The game engine was extremely good. It is the essence of BB. If you code another one from scratch, this will be another game, no BB anymore.
But, at the same time, it is an old code now, written by different people. It is sometimes said that it is an spaghetti code, impossible to understand. Maybe you can change some parameters, that is all that BBs can do now?
So, before we lose our time proposing and evaluating impossible changes to the game, BBs should answer this question: what type of changes are possible, and what type of changes are not possible?