Throw out all the the technical exercise books. Their exercises are often not directly transferrable to the real world, they rob precious time from the study of serious piano literature of the masters, some of the independence of the fingers exercises are downright dangerous, and they concentrate on fingers only, not the entire playing apparatus. It's far more beneficial to overcome technical difficulties as encountered in the actual repertoire, by creating your own exercises to help solve problems as you go along. That's what actually builds technique. The exceptions I would make would be all scales and arpeggios, which are indispensable to any pianist, as they can guide fingering in scalar passages in pieces.