Using iCloud on Verizon (Personal Hotspot)

I'm trying to figure out how to ensure that I don't accidentally backup and thus transmit massive loads of data via my iPhone via the cloud, whether via normal data usage or via tethering (usually my MacBook or iPad is tethered). Since I'm capped at 2GB for tethering, I've been concerned that my iPad/MacBook might initiate an iCloud backup while it's tethered and suck up the 2GB allotted in no time. Is this a valid concern or are these backups actually incremental in nature (where only changes are backed up after the original backup file has been generated)?

If you have a similar plan like me (unlimited data with a 2GB hotspot) how did you personally set up your iCloud settings?

Yeah I sounded too convoluted before.

Basically, I was trying to determine whether using "personal hotspot" was still considered Wi-Fi by iCloud, and if that's the case, theoretically my iPad/MacBooks could still send backups this way, not realizing the hotspot created is actually utilizing 3G coverage even unlike a normal Wi-Fi network. That's why I was a bit concerned.