Well. if you want to stick to single supply, you could use a charge pump to generate the small amounts of negative voltages you would need...
But, I do like the first variation and the instrumentation amps will give you better signal-to-noise, common-mode-rejection, etc. If you can, pick a low power single supply amp and run it off your Vref (may require a beefier voltage follower); that way the ADC inputs are guaranteed be to be with bounds.
Usually when someone calls me full of it, they're talking about something else.
