Of those, Flash is the only one that needs additional closed components.
There are ways to handle the Operator Wizard's role (possibly even ones that aren't broken by default, and can have their database updated when a problem is found with it)
several open-source handwriting input methods, and IIRC xvkbd can do completion, so the code's out there.
And unless I'm mistaken, Mer already includes (i.e., steals from existing Maemo install) bme.
You didn't mention it, but I'd put Skype with Flash; those are the two things I can see that have substantial impact on end-users and don't have plausible replacement paths.
As interim components until we get some of those worked out, I'm not averse to other things, but I don't see them as very important.