Hard to say. Clearly there are two camps. While we are indeed forcing an abstraction layer onto extension devs, that does not necessarily mean that we are going to use Chrome as the lowest common denominator with respect to extensibility.

Hopefully we can hit a sweet spot with respect to customization. WebExtensions are a superset of Chrome extensions, and do we have an open process for people to propose new APIs.

Some people are never going to be happy, but hopefully others will step forward and build some cool stuff.