Well, we disagree then. "just a matter of having the right design" is the part which stops 95% of games made from being classics. I see designing a GOOD game as a very difficult task and I also see it as the core problem with WoM. The engine no doubt got in the way of them adding more fun and so on but I don't think the disjointed nature of the core gameplay mechanics can be blamed on the engine (and if it can then that means Stardock basically wrote completely the wrong engine for the game they were trying to make, not just an inadequate engine, but the wrong engine).
What I was saying is that for the new team it is a matter of them designing a good game. You don't even need a computer to design a good game, you just need creative people. These are fundamentally two different problems. One is an artistic/creative problem and one is an software engineering problem. You can't really compare these types of problems on the same scale, art and creativity by its very nature is the intention of the design and not neccesarily a complex problem to be solved. Either a good game will be produced or it won't and whether or not its good or not doesn't speak as much to the "difficulty" as it does to a "failure of imagination/lack of creativity".
If you pose the question "can this new team design a good game" then the answer is yes, depending on their creativity. If however you ask the question "can they design a good game within the limitations of the engine" then you need answers about what has been fixed in the original engine before you can answer that question. And that is truly a complex math/programming/software engineering question with a binary answer.
Can the game produce truly random maps?
Will the maps have rivers?
Wiil the rivers link to the oceans and mountains and generally make sense for the topology?
What terrain types will be deformable for spells? (flood, volcano, earthquake, etc)
Does the game save state for each turn so you can do an end game replay?
Will the game have terrain that follows a logical pattern and resemble a terran topology?
Will the random map generator name, landmasses, geographic areas, etc ("Black Forest")?
Will the scale of cities, national borders, etc be taken into account in the map generator and initial player placement to give the player that fantasy kingdom feel, i,e some civilized land, some uncivilized? (mainly because wom turned into a Civ like map full of cities and stopped looking like fantasy and more like industrial revolution)
WoM could do very little of the above and while you may think that compared to the creativity neccesary to invent a great game this kind of stuff is trivial as a programmer I can tell you its incredibly difficult.