@Xenon-ud: My philosophy for development is simple. I like people to scratch their own itches. So if you have something that you want calibre to do, personally, go ahead and write the code for it. That way there is a greater chance that you will stick around to maintain that code in the future
If it is something large/invasive, it is best to discuss it here first.
As for bug reports, I tend to fix almost all simple bugs in the weekly release cycle, so bug reports are not a good place to get started.