I like stdlib++, but I also want to say it should remain as non-Python-dev endorsement
kind of thing. As a user and a library developer, I see pros and cons.

Official endorsement can lead to people to abandon whatever they are working
or make them feel excluded or unappreciated, which is not a very positive
thing to do.

On the other hand, there may only be a very limited number of stdlib replacement
people can vouch for easily.

For HTTP request, it is obvious that at the moment, Requests is the most widely
used library in modern Python codebase in the past several years.

For asyn-networking and asyn-task, Twisted and Tornado
are probably the best.
You might celery in the asyn-task just because many people who choose to
run asyn task will end up queuing.

For cryptography and security, what do you suggest? There are APIs cryptography
doesn't have yet but pycrypto or M2Crypto does. It isn't that neither are bad library,
I've used pycrypto and I am careful with using the API, but do we endorse cryptography
over the other two (the latter one is pretty dead based on its commit activity, I don't know).