TW is the best strategy games that have ever been made and still are to this very day. No one comes close.

When it comes to eye-candy I think it depends on why you play the game.
I play TW for the battles, the feeling of commanding large armies and seeing them battle it out.
Right now TW is getting closer and closer to that exprience and the eye-candy helps to create spectacular battles. The soldiers are actually starting to look like humans now and with MTW2 less like clones which will only increase the exprience.
This is probably the main objective right now for CA and according to CA this has always been their main objective.
Hopefully they won't ignore the other parts and I doubt they will.
MTW2 will be an improvement over RTW, I'm sure of it.
As TosaInu said, this isn't a new engine anymore. The problems in RTW was expected but they should have learned from those mistakes and I think they have. Sure it will still have bugs but hopefully they should be few and nothing serious.
Let's hope for the best.