Your better off knowing the efficiency of your brew setup. It may take a few brews before you really know. Then you can ajust your base grains to reach this each time you brew. Having good efficiency saves money. In my opinion that's why homebrewing craft beer is cost sufficient. My system is...
The yeast probably didn't get a good start, and the lower temperature may have prevented it from being agressive. Also your mash temperature has alot to do with how dry or sweet your beer will end up. The lower the mash temp. the dryer the beer will be, and opposite for higher temps. Lower...