Just my own experience....
I had iPad 2, 32gb wifi/ATT cellular model, running 6.1.2, jailbroken
My wife has iPad 3, 16gb, wifi only, running 6.1.3.
My son has iPad4, 16gb, wifi only, running 7.xx

I probably use iPad more than the two of them, lots of apps, and past year have not carried my laptop when on biz trips anymore. Except for the retina screen and slightly faster processor, not much difference btw the three models. And the iPad2 battery life is superior to the newer models, IMHO.

Wifi is widely available so don't have a subscription to data plan; seldom need data plan. BUT for emergency purposes, i.e. the last two major storms back east last year, enrolled each time when power outages occurred and it worked quite nicely.

I would suggest you look at either Vz or ATT model as they have better coverage. Also, keep in mind all iPads are unlocked so you can purchase third party international prepaid data plan if the need arises.

I also agree that you should get more rather than less storage.....

If money is not an issue, no reason not to get the latest and 'best'. If on a budget, get an older model and use the extra savings to get more storage.