I would also consider taking a look at Ola Hallegren's scripts. He has lots of documentation. The "recommended" maintenance is if fragmentatation is over 30%, rebuild, if it is between 5% and 30 %, reorg, and if it is less than 5% (or the table is very small) do nothing. Those numbers may or may not work for your environment.

http://ola.hallengren.com/sql-server-index-and-statistics-maintenance.html