If so, I'm volunteering to create the repository and import the current BIPs from the wiki there (and convert from wiki markup to markdown where necessary).
2) Time passes. Software for BIP drafts is developed, tested,
published, and publicly discussed in a typical open source manner.
Personally I think it is useful to have a number as soon as a BIP can be implemented, even if still in draft status; it gives something to refer to when mentioning a certain improvement proposal (in commit messages and such it could be called BIP xxx Draft).
I don't think we are at risk of running out of numbers to assign any time soon.