May work for some kind of projects, but may be a serious issue if you want to contain the number of features in your project
So branch. Nobody is forcing you to add the requested features to your main product... this will also encourage people to write good late-bound software - where extensions are trivial and play well together.
It's easy to branch the source code, but harder to branch the community, which can be one of the most important things. Sometimes a request for a feature comes with an implicit desire that it be in the main branch that everyone uses. Having good late-bound software would definitely ameliorate that.
So branch. Nobody is forcing you to add the requested features to your main product... this will also encourage people to write good late-bound software - where extensions are trivial and play well together.