I am working with ESRI ArcMap (10.2) and have set up a map page size for 40*60 inch. I created a pdf and printed, it looks good. Next I printed with lower size 11*17 but the place labels does not appear good on the map. Do I need to go again wit ArcMap and set page size for 11*17 and do all those works that I did for bigger size, create pdf and print it. Or is there anyway that can minimize my work load either at ArcMap or pdf environment?
I think you can check the 'Paint' tool and see if the label could be modified through that application. Export the map without modification in AcrMap and save as a image format, open it with Drawing and you could adjust the legend size. I always use this way to do some modifications like adjust the North arrow or place legend somewhere else. If you think it gets weird to directly drag the legend box to a larger size, you could simply select the legend and delete that, then create another annotation.
I'm not sure if your map itself looks good on the smaller size. If so, all the add-on things like legend and North arrow and scale-bar could be modified by this means. Hope this answer is helpful. :)