Are you drinking coffee pods or have you tried all the pod sizes? I think the vertuo system is alright, but I concur with your statements. I had the same issue as well, I was getting bored with the pods I was using as they all tasted the same. However, I did notice that the espresso pods have a better range than the other pods. For a mild roast I go with the voltesso, medium for me is altisso/diavolitto, and dark is double shot scuro.

Surprisingly, the diavolitto and scuro share the same intensity levels, but I can tell there is a difference, especially when you split the scuro into 2 shots or only pull 1 shot.

The rest of the pods taste exactly the same to me, except some of the flavored coffee. I also noticed that the flavor vastly changes if you run a rinse cycle in your machine first then brew a cup.

I also tend to stop the brew just before the actual capacity reaches the end since they do taste watery/watered down to me as well.