Was the German surface fleet a waste? I've seen arguements on more than two sides of that subject. My own opinion is that the surface ships weren't a waste. Some were wasted, but building them in the first place was a good idea.
Still, considering Susano's and other's opinions, Germany might have been better off without some of the bigger ships. The heavy cruisers were dogs, limited by cranky machinery that kept them in port a lot of the time. The newer light cruisers with the three triple turrets were overloaded and lightly built; not good sea boats.
Of course, Germany needed every available ship for the invasion of Norway. So, assume that the light and heavy cruisers are better designs. Say the design teams are conservative in the cruiser designs. The heavy cruisers have less cutting edge and more reliable power plants; the light cruisers might look underarmed, but they're available. And of course, the destroyers. The best thing for Germany's destroyer situation is to not have 10 of them sunk at Narvik. If that can't be done, there are still design changes, like not overgunning some destroyer classes.
If a victorious Bismarck makes it to Brest, would the battleship's presence and fame be enough to get proper Luffwaffe coverage of the German fleet there?
All this is not to say that I think Germany can win with these changes. Merely that the war will be different and the world we know may be different.