By the size of your var partition I think you have an iphone 4s so here's what I did to save some memory in that system partition:
Go to the first tab, the "+" tab and go tolanguages to remove, select all languages and that go back and press "voice control languages". It will remove all voice control and siri languages except for english. Than pres languages and it will remove all languages that can change the OS language except for english. Than go back and UNCHECK all the languages that you need for keyboard, do not remove japanese cause you won't be able to use emoji keyboard, just keep the languages keyboards that you need, than go back and press "keyboards".
You can also go to "manage wallpapers" and delete all the wallpapers that you want.
With these steps I managed to get 440 mb free in total from system partition.
Also go to "launch daemons" and disable "OTA update daemons", this will stop OTA updates from auto downloading while on wifi. Than do a clean to remove the ota already downloaded