Seems like you have a good detailed plan, you did not mention which MCS server you have in place. Make sure it is supported with CCM 4.1. Also, I assume you have no CTI applications such as AA, IPCC, otherwise you need to include this in your strategy. Also, all other 3rd party tools, such as paging. I would also run the upgrade assistant 4.1(3) as one of the first steps.
Chris