Your comments are mostly valid, but I disagree about Keras. Although it's marvellous for patching something together quickly, if you want to branch out at all then it quickly becomes an absolute mess.
Far better, in my view, is to work with the newer Estimators API. It is almost as fool-proof as Keras, but instead of trying to be a framework as such, the Estimators/learn API essentially just wraps up some of the boilerplate that you need with raw tensorflow, and internally looks fairly similar to the code you might write yourself. Consequently, it preserves the composability of TF far better than Keras.
Far better, in my view, is to work with the newer Estimators API. It is almost as fool-proof as Keras, but instead of trying to be a framework as such, the Estimators/learn API essentially just wraps up some of the boilerplate that you need with raw tensorflow, and internally looks fairly similar to the code you might write yourself. Consequently, it preserves the composability of TF far better than Keras.