If it's for the win (?), the most permissible is the one you choose. This is a extraordinarily competitive space. The sooner you make the choice and it's MIT, the sooner I personally put forth serious contribution time and the faster you grow in the broad and competitive ecosystem. Your main options are GNU All-permissive License, MIT License, BSD licenses, Apple Public Source License and Apache license.
It depends a lot on what you want the license to do, so I don’t really want to say one way or another.
IANAL, but my understanding is that code without a license effectively has an “all rights reserved” license in the U.S., meaning that it can’t be used for anything at all — even non-commercial work.
I will admit my ignorance on this topic, and I didn't want us to rush into selecting a license that is inappropriate.
Which one should we choose?