I know there are a number of issues about this and the maintainers of this module have firmly expressed that they have no intention to support the whitelisting of the elements defined in wysiwyg_filter_get_elements_blacklist() (primarily for security reasons). I understand and respect that.
Sometimes, however, this module is being used in a context in which users of a given input filter are fundamentally trusted (perhaps they're all employees of a small company) but you want to limit available markup so as to avoid crazy font colors, inline CSS, or other poor markup choices. But these are trusted users, so you're not too concerned about closing all possible attack vectors via tags like object, etc. So I propose employing an alter hook to allow the modification of the blacklist. This prevents less-knowledgeable users from inadvertently allowing these elements, but gives more-knowledgeable devs a way to leverage this very useful module for a wider variety of use-cases than is currently possible.