SO, WHAT SHOULD YOU BE READING?

During legal training you probably read enough law books, related material and class notes to last you a lifetime? But in every law university there is always that proffessor who always says ' You are a lawyer, read widely'
So do you mean that after all of this you still want me to do more? Yes, in fact.

There is a tale about Obafemi Awolowo that whenever he had to tackle a non-legal matter in court he would read up like a daemon and be able to come across as a professional in that field for the duration of the trial. In this tale it had something to do with medicine.

Where you assume that all you need to read and have time for is law books to prepare for cases, you may be right but even if you do that whatever legal reading you do is full of references to other areas not legal that your curiosity will lead you without.
But if it does not then you must go outside the fold so that you can find answers to your legal dillemmas or you will lack a connection with reality and practice your law largely for yourself.
Reading widely means you will be able to have conversations with people outside legal which is essential to generate business. You cannot always talk politics, sports and law with clients, it may seem like that is all you are capable of or it will make your conversations less engaging.

There is also the fact that a lot of the great achievements and events in some fields were borrowed from other fields. For example, The first conjoined twins, joined at the head from birth (craniopagus) to be separated and survive were the Binder twins from Germany and the operation was carried out at Johns Hopkins by Benjamin Carson (who by the way is being touted as the American republican presidential candidate for 2016).
He was able to solve the problem of one of the twins bleeding to death after separation which had always happened in previous operations by looking at a water tap (plumbing) and making the connection that once the babies hearts were stopped for an hour their blood would stop flowing the same way water stops flowing when you turn off the tap. All nerves could then be arranged after separation and death by exsanguination (loss of blood) would be avoided.

Also, the current structure of business is modelled on army military formations and a lot of our fashion items and jackets are also modelled on military uniforms.

The point of all this is, you need a basic education to have access to every idea you can to make sure you can contribute to legal affairs and your immediate environment, in philosophy, science, history and reading the newspapers really will not do.
As to a specific reading list you really will have to design your own programme and how you will fit it into your very busy schedule. However, accepting the idea is the very start and once you are convinced it is important you will find your way to fit it in.