Your plan is perfectly fine.
One thing to note is that the fare for Maglev is 50RMB. If you present an flight tickets for the same day then the fare is reduced to 40RMB. Return tickets are 80RMB.
The subway (line 2) will take 25 minutes and cost 4RMB.
Check the subway map here:
http://www.exploreshanghai.com/metro/