Offline single player mode

I think that when you are playing in single player mode or just collecting resources that you should have an option of playing offline. For those of us who play on cell service the data from playing online all the time. The data builds up fast. So offline should be an option.

you can crash the game with swarming data uploading, i say no

This will never happen. The online part of those actions is to prevent any abuse. If you could collect offline, that would also mean the mines/collectors would collect while offline and thus the game would be open to the device date changing method (change the date - the game will think 1 day passed and give the appropriate resources).
Unfortunately, everything will stay online.