Hi Ted:
I reccommend two approaches. One is to make sure all of your course objectives are included in the curriculum and that you make sure they covered thouroughly.
Secondly, you want to test only to material you've covered. That doesn't mean you can't ask eassy or critical thinking questions, but remember students aren't mind readers, so make it straightforward and direct.
Weight of different components is always a decision that's needed. A key I use is remembering I want to measure to what degree learning has occurred. So , perhaps, looking at the different couyrse components to decide what best measures what's been learned will guide what weight to put on them.
Good luck. These modules may help give you ideas that will be helpful to you as well.
Regards, Barry