REST APIs in Go - using net/http vs. a library like Gorilla

I see that Go itself has a package net/http, which is adequate at providing everything you need to get your own REST APIs up and running. However, there are a variety of frameworks; the most popular maybe say Gorilla.

Considering that one of the main things I need to do going forward is to build REST APIs that will access some backend storage (databases, caches, etc.) to perform CRUD operation, is it good to go with Go's standard library itself, or should I consider using some frameworks?

Normally, people write a new library or framework which solves the problem present in the existing library. But a lot of the frameworks also tend to make things worse when actual demands are simple.

So I have few questions:

1. Is the basic library in Go language good enough to support basic to moderate functionality for REST?

2. If I do end up using the inbuilt library and tomorrow have to change it to use some framework (like a Gorilla), how difficult/costly would that be?

3. Are frameworks really addressing the problems or just making simple problems complex?

I would be extremely grateful for someone to share his thoughts here (who has been through making this choice himself) while I research more of my own.