After reading your letter (which as everything you write was beautifully articulated), I had the following thoughts which I hope you could comment on at some point. Not that I'm trying to justify a ban. But isn't there something to each section of Judaism needing to present itself with a certain conviction and fire that this is the only way. Otherwise if each side is rationally discussed it kind of dilutes the other, if I'm making sense.
As far as the Torah Umaddah issue, I consider myself a Hirschian, and far from what I believe Torah Umaddah represents. It seems to me that all these classifications are more cultural than substantial, (how many people classified as one or the other have put 1/1000th of the amount of thought you did) and if your message is one of rationality than it would be best to do away w/ these stereotypes.
With regard to your first point, it is essentially correct; charedi Judaism, by its very nature, is not able to tolerate the existence of other groups laying claim to legitimacy. I think that everyone else therefore has to tolerate a certain amount of intolerance. However, the question is how much the charedi world needs to fight other approaches, especially when it is possible for them to tolerate it as "kiruv" or whatever.
Your second point may well also be legitimate. To be sure, most people in all communities have not given serious thought to any of these issues. Because this issue is so important to me, I may well be blowing it out of proportion. Still, I find that there are many, many differences between Charedim and non-charedim which relate to this issue.