While adding printer memory is a good idea to help the printer handle large and complex jobs, it won't necessarily free up the person's computer any faster. Depending on the model of printer, it may become apparent when spooling multiple large print jobs, that the printer is forcing the computer to spool one job at a time.
In this case, it may be very useful to print to a server, rather than directly to the printer. This allows the user's computer to be freed up immediately after the job is printed. The jobs are held in queue by the print server, and individually spooled to the printer as the printer becomes ready for each job. Meanwhile, the user is free to reboot, shut down, disconnect from the network, etc... without affecting the print jobs that are being processed. Additionally, multiple large print jobs can be "load balanced" across several printers, allowing for a faster overall completion than if only one printer is used.
Below is a link to a free linux-based print server called CUPS which is included as part of the eBox platform. However, there are many other solutions out there that can serve the same purpose. An old spare computer should serve nicely as a server, and provide any office printing numerous large documents (law offices, accounting offices... etc) with a noticeable improvement in productivity.
Good luck!
http://www.cups.org/
http://www.ebox-platform.com/
http://www.howtoforge.com/running-a-file-and-print-server-with-ebox-on-ubuntu8.04-server