The tables and views shouldn't have much impact (they are basically just formatting of the underlying data when it's being displayed.
I just took a 500 task project, 26 resources, year-long schedule, added 3 baselines to it (as well as a couple of interim plans) and barely get to 3MB.
You might want to send me a sanitized version of the plan so I can take a look.
View | Gantt Chart, display the ID column and then copy it and paste it over the Task column
View | Resource Sheet, display the ID column and then copy it and paste it over the Name column
File | Properties and clean up anything there.
Send it to PDQBach4100 at H0T MA1L and I'll take a look at it.