After switching solely to a MiIf pad, with a Nexus 7 to replace my ailing Macbook, this first two days internet usage came as a shock. About 1.28GB of data or around $12 of the $40 data card purchased. Clearly that won't do! At that rate, I'd be bankrupt by the end of a month!
The new paradigm is here to stay for the moment however. The trick now is to supplement MiFi usage with free public WiFi usage. Most of that data usage came from two sources - Google Play and Google Services with quite a chunk also coming from Gallery.
The solution was to disable auto-updates and the gallery was just updating to match what's in the photo library on the google account. It'd be a fair guess that once the galleries match, data usage will be minimal. Clearly this device should have been set up over public WiFi.
In use, it all seems quite good. The smaller size combined with a keyboard cover ($10 from eBay) seems to work quite well. The blogging app isn't that great - it won't permit article descriptions to be entered nor for articles to be shared via Google Hangouts, nor will it allow a posting location to be selected rather than being arbitrary. It also won't permit posts to be scheduled - they're always posted instantly which is not really that desirable.
In general though, the system of using a Nexus 7 and a MiFi pad seems to be working quite well with just a few minor teething issues. We'll have to see how a longer immersion works.