Beside the risk of reaching the sizelimits soon in Git you can do the following:
	- Remove unused (marketplace) modules
 
	- Remove all excluded items.
 
	- Replace duplicate pages with snippet calls.
 
	- Find Advanced for Unused Items and remove them (carefully, they may be used)
 
	- Replace older UI attributes and conditional visibility with dynamic classes
 
	- Find older Mendix construction like separated create and change actions and combine them with modern structures.
 
	- Find for duplicate microflows and remove one.
 
	- If marketplace place modules like community commons are used for some java actions, move them you another module and remove the marketplace module.
 
 
Yes, All very timeconsuming tasks.
 
After this use a tool like db-browser for sqlite
	- Open the mpr-file (which is a sqlite database)
 
	- Tools/Compact the database, select all databases.
 
 
Things that don't work:
	- Remove widgets
 
	- Remove unused jars from the userlib, usefull anyway
 
	- SVN Cleanup
 
 
Big alternative is
	- Split your app in multiple app (license needed)