Can software ever be perfect? Of course not. There will always be the desire for improvement and bug fixing.
Software tools that are most often never perfect are those that need to link up with each other across the vendor divide. We should not complain though. We should make the best of it, and do our best.
Apple have been generous in the latest version of iBooks Author by providing 2 ways that we can get out content from Adobe InDesign into the free 'multi-touch' authoring environment. But, neither of these 2 methods are perfect and we need to develop our skills of patience and perseverance in order to achieve our goals.
If you need to tweak the styles of your ebook created with the iPad in mind then you can (with a bit of magic) set up Dreamweaver as a useful wysiwy(almost)g tool.
Dreamweaver, is, of course a web development and design tool. It will normally handle (x)HTML without any change. It will also allow you to edit other code and even XML. It will not edit the contents of a ZIP file (this is what a normal ePub package is) unless it is unpacked.