Adjusting the info package size would be helpful...
But don't go with INCREASING the numbers, It's all depends on the your extract structure size, source system memory settings.
I would suggest to do some trail in DEV/QUALITY systems with enough data.
I remember playing in production itself for CRM - 0BPARTNER extractor - we actually reduced the number of records to be extracted per package to improve the performance - we did see the impacts.
First calculate how much is your current package size by number of records extracted per package now with your extract structure size..and then play around..sure it will help unless you DON'T have any excessive ABAP code user exits.
Let us know if you need further help on this