typically, the only housekeeping you would need to do is clearing temporary files and moving or removing files that you, yourself, put on the machine. It is not recommended to remove anything that is placed in the system via the OS. You can remove items such as updates that have been downloaded, but that also has a special channel that tells the system that the software is no longer available on the disk. Random deletion is never recommended.
As mucks said, I would simply reduce the amount of disk space used if you don't want to keep that many restore points.