It is about a 20-30 minute walk from dock to Cable Car. We did a combo that included Monte, Botanical Gardens and cable car.
We loved Malaga - took the shuttle to be dropped near the centre and walked to the Roman fort then up to the castle at the top. You can see the bull ring and all of Malaga from this point.
Cathedral was very impressive as well.
This was our surprise of the cruise as we have flown into Malaga but never looked around.