Game budgets are a weird thing. It's not simple a case of "better looking game = more expensive". Budget comes down to two things: production costs, and advertising.
Production costs can be influenced by numerous things that aren't necessarily tethered to hardware power. For example, I may wish to have a tremendous amount of recorded dialogue in my game, as well as cinematics to tell the story. Hiring script writers, voice actors, cinematic directors, cinematic animators, sound editors, recording equipment and more is costly and time consuming, and thus a lot of money can be eaten up by these kinds of things.
Most 'expensive' games are expensive because there's so much work put into making the games. They're 'big' games. Lots of features, lots of intricate directing and animation, lots of audio, lots of everything. It's less about how detailed individual assets are and more about how many of those assets need to be made.
The funny thing is that stronger hardware can, in theory, lead to cheaper development when certain parts of game designed become streamlined and easier to control. On dated hardware rigging up a complex and gorgeous looking environment for a cinematic might require collaboration between programmers and artists as they try and 'fake' how good the scene will look will maintaining optimisation. Lots of custom assets in lighting, shadows and lots of custom code specifically for making that particular scene look the way it does. On stronger hardware we might be able to render all of that in real time, allowing the artists to single handedly take the reigns as no programming, engine or custom asset hurdles are introduced.
Streamlining the development process aims to give developers more control and flexibility over their working environment. This is one aspect of Unreal Engine 4 Epic is really pushing. They want to give artists and designers the freedom to experiment and work on game code, testing it as they play and seeing accurate flowcharts of a game's functions, without having to compile the code and jump through hoops just to see if their level looks right, or that character animates correctly, or that encounter is balanced and fun to play.
Big budget blockbusters will still cost a stupid fortune, probably moreso next generation than now for the same reasons that Hollywood blockbusters are expensive. But strong hardware and streamlined engines come with their own advantages that can lessen the burden of development, decrease the need for meticulous engine tweaking, and actually speed up development work, thus saving time and money.
But again this is dependant on not what the Wii U is, but what position the Wii U has in the market. Those same smaller scale shock horror games can be made for the Xbox 720 and PlayStation 4, and if those consoles have a decent market penetration with a healthy software market. Same goes for PC. It doesn't need to be one or the other, blockbusters versus low budget. Platforms can sustain both quite comfortably.
If the Wii U can sustain a software environment for games with lower budgets then sure, we'll probably see a lot of games like that coming to the platform. But if they sell like arse, much like they often did on the Wii, developers wont give a shit as they can make their money easier elsewhere.