I've had a few instances where I've build Fedora packages and tested them so that they work well. However, on other platforms they failed on simple dependencies because certain items where i386 architecture only.

I would love to see the ability within the build system to be able to:
1) Extend 'make build' to do an install of the built application. Since we have the full build environment it would seem simple to then run an installation to catch any missing dependencies
2) Add a separate command 'make install' that will install in a mock environment on the target application and report success/fail.