We're currently using MBUnit for both unit testing and UI testing. For UI testing setup cost for test matrix axes are pretty high (login, browser instance, navigate to page etc). In order to avoid setting up these for each test case we are partly relying on AssemblyFixture to manage some of them.
However because it's not possible to filter out certain cases where they are not applicable to certain combination, it's not possible for us to really use such optimization. So currently we are doing some of the setup per test-case, horribly inefficient.
We could put if statements inside test code to check for correct combinations but we don't desire that either. It pollutes test code.
How do you guys do such optimizations? or test matrix management? Is there a better practice, in another testing framework?