I agree with you on the point that actually getting to write an engine (whether it is universal or specific) is crutial. You'll always end up having a loop where you will constatly update the game based on player input; that point of stability denotes that you have an engine running.
But I would definately write a specific engine for each game I would make; that's just a matter of personal opinion :D
But I would definately write a specific engine for each game I would make; that's just a matter of personal opinion :D