So what is the problem with creating a new blockchain dedicated to this project, if you are so convinced that it will succeed (apart from the fact that it would be the nth blockchain, and growing)? Why insist on using Bitcoin blockchain, especially when cons have been very reasonably argued already?

About the project itself, looking at the links you shared, you have done a good job so far IMO. You are addressing a real problem that has been giving headaches for a long time. I simply want to share my concern about creating a new problem by trying to solve an old one.